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From Wikipedia, the free encyclopedia
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Straw-necked Ibis
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Pelecaniformes
Family: Threskiornithidae
Subfamily: Threskiornithinae
Poche, 1904
The ibises (collective plural ibis;[1] classical plurals ibides[2][3] and ibes[3]) are a group of long-legged wading birds in the family Threskiornithidae.
The word ibis comes from Greek and Latin, and probably from Ancient Egypt.[4]
Species in taxonomic order[edit]
There are 28 extant species and 2 extinct species of ibis.
An extinct species, the Jamaican Ibis or Clubbed-wing Ibis (Xenicibis xympithecus) was uniquely characterized by its club-like wings.
In culture[edit]
The African Sacred Ibis was an object of religious veneration in ancient Egypt, particularly associated with the deity Djehuty or otherwise commonly referred to in Greek as Thoth. He is responsible for writing, mathematics, measurement and time as well as the moon and magic.[5] In artworks of the Late Period of Ancient Egypt, Thoth is popularly depicted as an ibis-headed man while consumed in the act of writing.[5]
At the town of Hermopolis, ibises were reared specifically for sacrificial purposes and in the Serapeum at Saqqara, archaeologists found the mummies of one and a half million ibises and hundreds of thousands of falcons.[6]
According to local legend in the Birecik area, the Northern Bald Ibis was one of the first birds that Noah released from the Ark as a symbol of fertility,[7] and a lingering religious sentiment in Turkey helped the colonies there to survive long after the demise of the species in Europe.[8]
The mascot of the University of Miami is an American White Ibis. The ibis was selected as the school mascot because of its legendary bravery during hurricanes. According to legend, the ibis is the last sign of wildlife to take shelter before a hurricane hits and the first to reappear once the storm has passed.[9]
A short story "The Scarlet Ibis" by James Hurst uses the sable-hued bird as foreshadowing for a character's death and as the primary symbol.[10]
The African Sacred Ibis is the unit symbol of the Israeli Special Forces unit known as Unit 212 or Maglan in Hebrew: מגלן.
Moses used the Ibis to help him defeat the Ethiopians. [11]
Species images[edit]
1. ^ "ibis". Dictionary.com Unabridged. Retrieved 6 October 2009.
2. ^ C. A. M. Fennell, ed. (1892). The Stanford dictionary of Anglicised words and phrases. Cambridge: Cambridge University Press. p. 453. OCLC 1354115. Retrieved 6 October 2009.
3. ^ a b Pierce, Robert Morris (1910). Dictionary of Hard Words. New York: Dodd, Mead & Company. p. 270. OCLC 4177508. Retrieved 6 October 2009.
4. ^ Chambers Dictionary
5. ^ a b Birmingham Museum of Art (2010). Birmingham Museum of Art : guide to the collection. [Birmingham, Ala]: Birmingham Museum of Art. p. 65. ISBN 978-1-904832-77-5.
6. ^ Fleming, Furgus; Alan Lothian; Duncan Baird Publishers. The Way to Eternity: Egyptian Myth. Amsterdam: Time-Life Books. 1997. pp. 66-67
7. ^ Shuker, Karl (2003). The Beasts That Hide from Man: Seeking the World's Last Undiscovered Animals. Cosimo. pp. 166–168. ISBN 1-931044-64-3. "Dreams of a feathered Geronticus"
8. ^ Beintema, Nienke. "Saving a charismatic bird" (PDF). AEWA Secretariat. Retrieved 11 December 2008.
9. ^ Hurricane sports
10. ^ The Scarlet Ibis
11. ^ http://www.gospeldoctrine.com/NewTestament/Acts7.htm
External links[edit]
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Iron sight
From Wikipedia, the free encyclopedia
(Redirected from Iron sights)
Jump to: navigation, search
Iron sights are a system of shaped alignment markers (usually metal) used as a sighting device to assist in the aiming of a device such as a firearm, crossbow, or telescope, and exclude the use of optics as in telescopic sights or reflector (reflex) sights.[1] Iron sights are typically composed of two component sights, formed by metal blades: a rear sight mounted perpendicular to the line of sight and consisting of some form of notch (open sight) or aperture (closed sight); and a front sight that is a post, bead, or ring. Civilian defensive, hunting, and police firearms usually feature open sights, while many military battle rifles employ aperture sights. On many firearms the rear sight is adjustable for elevation or windage.[2]
The earliest and simplest iron sights are fixed and cannot be easily adjusted. Many iron sights are designed to be adjustable, so that the sights can be adjusted for windage and elevation. For precision applications such as hunting or sniping the iron sights are usually replaced by a telescopic sight. Iron sights may still be fitted alongside other sighting devices (or in the case of some models of optics, incorporated integrally) for back-up usage.
In the case of firearms, where the bullet follows a Newtonian trajectory, front and rear sights must be aligned with the line of sight of the shooter, calibrated to the distance of the target and the trajectory of the bullet, so that the bullet hits the target. Iron sights provide horizontal and vertical reference points that allow the shooter to train the weapon.[2]
Even a tiny error in the angle of sight alignment results in a trajectory that diverges from the target on a trajectory directly relative to the distance from the target, causing the bullet to miss the target; for example with an Olympic 10 metre air rifle shooter trying to hit the 10 ring, which is merely a 0.5 mm diameter dot on the target at 10 meters and with a 4.5 mm diameter pellet, an error of only 0.2 mm in sight alignment can mean a complete miss (a 3 mm point of impact miss). At 1,000 meters, that same 0.2 mm misalignment would be magnified 100 times, giving an error of over 300 mm (1500 times the sight misalignment of 0.2 mm). (Calculations assume a 660 mm sight radius or sighting line) A long sighting line helps to reduce eventual angle errors and will, in case the sight has an incremental adjustment mechanism, adjust in smaller increments when compared to a further identical shorter sighting line.
Types of sights[edit]
Iron sights can be broken into two basic categories that include most types: Open sights which use a notch of some sort as the rear sight, and aperture sights use some form of a circular hole. Sights of both types can also be classified as fixed sights or adjustable sights.
Fixed and adjustable sights[edit]
A tangent sight on a CZ 452 rimfire rifle, with calibrated markings for ranges out to 300 meters
Open sights[edit]
Advantages and disadvantages[edit]
Aperture sights[edit]
Aperture sights, also known as peep sights, range from the ghost ring sight, whose thin ring blurs to near invisibility (hence ghost), to target aperture sights that use large disks or other occluders with pinhole-sized apertures. In general, the thicker the ring, the more precise the sight, and the thinner the ring, the faster the sight.[2] The image to the right shows a shooter's eye view of the sight picture taken through large and small diameter apertures. The large diameter aperture provides a much brighter image of the target, and the ghosting of the rear ring is evident. The smaller aperture, while providing a much darker image of the target, provides a much greater depth of field (see pinhole camera for an explanation of this effect), yielding a much sharper image of the target.[2] The theory of operation behind the aperture sight is that the human eye will automatically center the front sight when looking through the rear aperture, thus ensuring accuracy.[2]
Ghost rings[edit]
Target aperture sights[edit]
Rear aperture of a BRNO target sight. Note large disk and small aperture.
A 10 metre air rifle target diopter and globe aperture sight picture
Shotgun beads[edit]
Glare reduction[edit]
Contrast enhancements[edit]
Self-luminous tritium-illuminated night sights of a SIG SG 550 rifle.
Tritium-illuminated handgun night sights.
Green fibre optic contrast enhancement rods used in an adjustable open sight rear element.
• White outline rear: A contrast variation which uses a dot front sight with a thick and bright white outline around the rear sight notch.[4]
• Sight inserts: Popular on revolvers, this enhancement consists of a colored plastic insert in the front sight blade, usually red or orange in color.[6]
• Gold bead: Preferred by many competitors in IPSC and IDPA shooting.[3]
• Night sights: On tactical firearms, the contrast enhancements can consist of trasers containing tritium gas, which emit a dim light due to the radioactive decay of the tritium, and fluorescent material. Self-luminous tritium sights provide vital visibility in extremely low light situations where normal sights would be degraded or even useless.[7] The tritium glow is not noticeable in bright conditions such as during daylight however. As a result, some manufacturers have started to integrate fiber optic sights with tritium vials to provide bright, high-contrast firearms sights in both bright and dim conditions.
Concealed carry[edit]
Specific to handguns is the issue of concealed carry. Police and military personnel generally carry their handguns in open holsters that provide easy and unobstructed access. Where concealed carry by citizens is allowed, those citizens often choose or are required to carry their firearms hidden, under clothing or some other form of cover (such as an untucked shirt, fanny pack or purse, for example). The high contrast, sharp edges popular with target shooters can be dangerous on a concealed firearm—-not only can they tear skin and clothing when drawn, but if they become tangled during the draw, entanglement can have lethal consequences for the shooter.
The challenge a sight designer faces for a concealable handgun is to pick the right compromise between high visibility and minimum hindrance. Rather than the vertical or even undercut front sights found on target handguns, the front sight of a concealed carry gun will be ramped, or sloped gradually upwards from the rear to the front. The rear sight will not be a vertical plate, but will have depth to also provide a gentle slope, and the sight will fit the gun more closely, with no gaps or overlaps to snag, or to collect dirt and sweat which can cause corrosion.
Design criteria for concealed handgun sights also consider the challenging conditions under which the sights may potentially be used—-low light, time pressure, close range, and with the operator under significant stress due to imminent threat. Some unusual solutions have been devised, such as the trapezoidal sights used by Steyr M (shown as G in Types of Iron Sights), or the "gutter sight" used by the highly modified ASP S&W model 39. Colt's Manufacturing Company also produces a line of sub-compact pistols with what they call a trench sight; it is simply a channel cut into the length of the top of the slide, for fast but short range target acquisition.
Adjusting for accuracy[edit]
If the sights are not aligned correctly, then the sights should be adjusted to bring the line of sight to meet the point of impact. Theoretically, this can be done with a single shot—clamp the firearm into a vise, fire one shot, then adjust the sights so they are pointing at the hole in the target. In reality, it generally takes a number of shots to establish a group, then the sights are adjusted to move the line of sight closer to the group, and the process is repeated iteratively until the sights are correctly aligned.
The general rule is the rear sight is moved in the SAME direction you wish to move the point of impact. For example, if the point of impact is LEFT and BELOW the target, and you wish to move the point of impact to the center, then move the rear sight RIGHT and UP. The front sight moves the opposite direction, so it would move LEFT and DOWN.
Detailed instructions for adjusting the sights:
• To move the line of sight DOWN (the shot hit BELOW the point of aim) the REAR sight is RAISED or the FRONT sight is LOWERED.
• To move the line of sight UP (the shot hit ABOVE the point of aim) the REAR sight is LOWERED or the FRONT sight is RAISED. (Example below)
• To move the line of sight LEFT (the shot hit LEFT of the point of aim) the REAR sight is moved RIGHT, or the FRONT sight is moved LEFT.
• To move the line of sight RIGHT (the shot hit RIGHT of the point of aim) the REAR sight is moved LEFT, or the FRONT sight is moved RIGHT.
Many target sights have click adjustments, where a detent in the adjustment screws allows the sight to move the line of sight a certain angular distance with each click. This distance is usually specified in minutes of arc, which translate to approximately 1 inch at 100 yards. On a firearm with 1 minute clicks, then, it would take 1 click to move 1 inch at 100 yards, 2 clicks to move 1 inch at 50 yards, 4 clicks to move 1 inch at 25 yards. If click adjustments are not available, or the click interval is not known, then the distance to lengthen or shorten the sight for a given point of aim adjustment is:
D1 / R1 = D2 / R2
For rear sight adjustments:
• D1 is the distance between point of aim and point of impact.
• R1 is range from front sight to target.
• D2 is the length the rear sight must change by.
• R2 is the distance between front and rear sights.
For front sight adjustments:
• R1 is range from rear sight to target.
• D2 is the length the front sight must change by.
• R2 is the sight radius distance between front and rear sights.
This formula calculates the MAGNITUDE ONLY of the sight height change; refer to the instructions above to find the correct direction for the adjustment (front or rear sight, longer or shorter). Likewise, all distances must be in the same units. That is, if a change in inches to the sight height is desired, and one is shooting on a 100-yard range, then R1 (100 yd) must be converted to inches (100 × 36 = 3600 inches) before using this distance in the equation.
An example: Consider a rifle with a distance between front and rear sights of 26.25 inches, firing on a 50-yard (1800 in) range, with point of impact 5.3 inches too high on the target, having a front sight blade that is 0.505 inches high mounted in a dovetail. How much must the front sight blade height be changed by to fix this problem? (It will be assumed that the muzzle of the rifle intrudes into the range space for following typical gun range safety protocols, and the rear sight is hence 50 yards from the target.)
D2 = R2(D1/R1) = 26.25(5.3/1800) = 0.077" (magnitude of change to front sight height)
Since the gun is hitting too high, the front sight must be lengthened by this much per the instructions cited previously; hence, the front sight must be replaced with a blade that is 0.505" + 0.077" = 0.582" high. With this correction, the rifle will hit the desired point of impact, all other factors being equal.
See also[edit]
1. ^ - iron sight a metallic sight for a gun as distinguished from a sight depending on an optical or computing system
2. ^ a b c d e f g h i j Hawks, Chuck. "Choosing the Right Sight", Chuck Hawks Web site. Retrieved July 24, 2008.
3. ^ a b c "Description Of Sights" Novak Sights Web site. Retrieved July 29, 2008.
4. ^ "Sight Accessories - .126 White Outline Rear Sight Blade Kit" Smith and Wesson Web site. Retrieved July 29, 2008.
5. ^ "Heinie Straight Eight Sights" Heinie Specialty products Web site. Retrieved July 29, 2008.
6. ^ "Handgun Sights" Kimber of America Web site. Retrieved July 29, 2008.
7. ^ Hawks, Chuck. "AmeriGlo Independent Light Tritium Night Sights", Chuck Hawks Web site. Retrieved July 29, 2008.
8. ^ "Novak Fiber Optic Sights" Novak Sights Web site. Retrieved July 29, 2008.
External links[edit]
• Additional BRNO target sight images 12 3
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Chemistry: Electrochemical Cells
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About this Lesson
• Type: Video Tutorial
• Length: 9:29
• Media: Video/mp4
• Use: Watch Online & Download
• Access Period: Unrestricted
• Download: MP4 (iPod compatible)
• Size: 101 MB
• Posted: 07/14/2009
This lesson is part of the following series:
Chemistry: Full Course (303 lessons, $198.00)
Chemistry: Electrochemistry (12 lessons, $19.80)
Chemistry: Galvanic Cells (6 lessons, $11.88)
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When last we spoke, we had a brilliant idea. We were going to take advantage of the fact that copper reacted with silver plus to make copper 2 plus and silver and we were going to harness the electrical energy involved in this reaction. The idea was if we could separate the copper and the silver from each other, we'd be able to pass the electrons through a wire rather than directly through a solution and be able to use that electricity to run a motor or light up a light bulb or do something. So, we wanted to keep things simple so that we could keep things at standard state. We went ahead and designed something where we'd have 1 mole per liter of solution of the copper 2 plus and the silver plus, as well as chunks of copper and silver. So everything was at their standard states. We'd hook up a wire between the copper and silver and the sad news was that this didn't work. And the question I left you with was why not?
Well, I know you haven't got much sleep since last time we talked, but the reason is that as electrons start to move from this cell to this cell, and copper starts to become copper 2 plus, and the first few atoms of silver start to precipitate out to make silver metal, what happens is that the accompanying ions start to build up charge. In other words, this wasn't just silver plus; it was silver plus with a nitrate. Over here, the copper, once it formed copper 2 plus, that copper 2 plus doesn't have an anion accompanying it. What we need to do is somehow get the nitrate anions, the negatively charged anions, over to this cell to account for the charge that we're building up here. And that's the reason why our idea, as we originally devised it, would never work. We could pass the first couple of electrons and then that's it. We're going to build up charge, and remember, one of the fundamental things we know about nature is nature does not like separation of charge, and that's exactly what we're doing.
So, we need to prepare a path to get nitrate from this cell back over to this cell. But of course, we also want to not mix this copper solution over here. Otherwise, we're going to just get the chemical reaction that we saw in the beaker a few moments ago. So, the answer is - kind of the practical solution to this is - we want to have some type of a permeable membrane, but one that slows down the fusion enough so that we don't let the copper get over here. Now another way to accomplish the same thing is if we have a path in which ions can flow through but the point would be that the path would be long enough that we don't allow the copper 2 plus that's formed to get over into this other side, because then the copper and the silver would react directly.
So what's done in practice, then, is we use something called a salt bridge. Imagine a piece of glass tubing used here to connect the silver and the copper cells, or half-cells. And then at the ends of the tube, we'll put in a plug of cotton or something to prevent solution from easily flowing in and out. But, again, the cotton has small channels where ions can flow. Finally, what we're going to do is put in an electrolyte in this solution so that we allow for, if not copper 2 plus ions, at least the sodium cations that are in this electrolyte - like it might be sodium nitrate, for instance - to start to migrate towards the negative charges here and the nitrates to start to move into the salt bridge while other nitrates move out of the salt bridge.
So the details of this are not important. What is important is it allows us to move charges from this cell to this cell in the sense that we balance out the charges that were moving from this electrode to this electrode. In doing that, we complete a circuit and, indeed, we can get work from this circuit. And, in fact, this is essentially the essence of a battery. This is a 9-volt battery here. We'll talk more about batteries - as an example - something called a dry cell. It's not a wet cell like I'm showing you here. We'll talk lots more about what different batteries there are and how they're designed a little bit later. But the basic idea of what we show on paper here is exactly what a battery is. It's harnessing chemical energy to use in the form of electrical work, in this case.
So let's define our terms here again. This is called a galvanic cell. And a galvanic cell is a cell that will run spontaneously. You'll see we'll contrast this in a moment. It's a cell that can run all by itself once we hook it up. That just simply means the chemical reaction - the net chemical reaction we're doing - is a spontaneous reaction. We know all about that now. And so, we will define that anode as the electrode where oxidation occurs. So in this case, remember, the oxidation is copper metal going to copper 2 plus, and so that is where the anode is. In this case, that's what we defined. And normally, by convention, people will have the anode on the left side, although, I'm not a big subscriber to that convention. I think it's kind of pointless to remember something like that. Just remember that anode always is where oxidation is. That's the important thing to remember.
Now, in contrast, what's going on over here is a reduction. We call that the cathode. So the definition of a cathode is where the reduction's occurring. That's the electrode where the reduction's occurring. And, let's see, what else can I tell you about the cell? Pretty much, that's it. We can either use this electrical current to do work or, what we'll do a little bit later is take out this motor - take away the load - and just simply measure what the potential is to do the work. And we can actually measure a voltage across this, so we'll get to that in just a moment. For now, I just want to introduce you to the galvanic cell, and we'll compare this to an electrolytic cell.
An electrolytic cell is the opposite idea. An electrolytic cell is a cell where you're running the current in the opposite direction that it's normally inclined to go. So if we take our copper and silver cell, just like we had before, but we replace the motor with a battery such with enough potential to force electrons to go in this direction rather than in the opposite direction. We still need our salt bridge to make sure that we complete a circuit, but then let's look what's going on. If we're forcing electrons out, what we're doing is pulling electrons now out of this electrode. That means that now the oxidation occurs over here. So this becomes the anode now. We have silver metal going to silver plus plus an electron. The electron is being pulled out into the battery here. And notice that the anode is now on the right side, in an electrolytic cell. And again, all I care about, at least, is that you know that an anode is where oxidation occurs. That is still true, regardless of what kind of cell we have.
Over here is the cathode now. This is where the reduction happens. And what is the reduction in this case? Copper 2 plus plus 2 electrons goes to copper metal. So we're reversing the process and we're plating copper metal out over here and we're chewing up the silver in the process. Now, who in their right mind would want to do this and consume silver in order to get copper metal? Probably nobody. You could think of a lot of other materials that you could use instead of silver as a way of plating copper out. But the basic idea here is actually used industrially. This is the essence of electroplating, and we'll have more to say about that. When people talk about spoons that are coated with silver or gold-plated jewelry and so forth, it's this basic idea of how that is done.
So, again, we'll come back to that later. Right now, it's just the definition of the terms. Electrolytic cell, again, is something running the opposite direction that it normally wants to run in, whereas the galvanic cell, it was running the direction that would be the spontaneous reaction. So we're going, seemingly, against nature here - apparently, in violation of Gibbs free energy, but actually not, because we're forcing it, now, with an even greater free energy in the opposite direction, if you will, with this battery forcing this situation to go in reverse.
So, again, that's an electrolytic cell, a galvanic cell, and indeed, our basic notion that we can take certain chemical reactions, split them into pieces - what we'll refer to as half-cells - and get useful work out of them. Our next step, then, is to actually remove that motor and measure the potential to do the work rather than actually do the work. That, as you might guess, is going to be related to the driving force of the reaction. We're going to make a fundamental tie between Gibbs free energy, which describes how reactions desire to go to equilibrium, and the potential that we can measure across those wires before we connect it up and have the reaction occur.
Galvanic Cells
Electrochemical Cells Page [2 of 2]
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Mapungubwe History of Africa Denied
For Centuries the rich History of South Africa dating back about 2000 years was hidden from its people. The fact that Bantu speaking peoples of the region had a highly civilized existence hundreds of years before the first Europeans arrived was simply too much for the oppressive government of the day to bear.
gold_artifacts.jpg (13535 bytes)To the left some of the gold artifacts uncovered. The events above unfolded close to the confluence of the Shashi and Limpopo rivers in the Messina district where two hills separated by a valley on the land Greefswald - the one named Bambandyanalo and the other Mapungubwe. In 1932 a man named van Graan (farmer - prospector) discovered that the summit of the Mapungubwe Hill was littered with pottery, upon closer inspection and further digging two kilograms of pure gold foil, along with beads and ornaments was uncovered. The pure gold foil artifacts were each meticulously tacked with tiny golden nails that covered the now perished wooden rhinos and elephants.
Gold_jewelry.jpg (12350 bytes)Left the gold necklace. The findings not only provided evidence of early gold smelting in southern Africa, but of the extensive wealth and social differentiation of the people of Mapungubwe. At first Van Graan decided to keep quiet, but later the find was reported at the University of Pretoria. Greefswald was bought by the government of the day. Although the University of Pretoria excavated the site ever since 1932 it was kept top secret. The findings provided evidence contrary to the racist ideology of black inferiority that underpinned apartheid.
According to the archaeology department at the University of the Witwatersrand, Mapungubwe represents "the most complex society in southern Africa and is the root of the origins of Zimbabwean culture". It is testimony to a civilization that existed and flourished years before European occupation.
Mapungubwe was home to an advanced culture of people. The civilization thrived as a sophisticated trading center from around 1200 to 1300 AD. It was the center of the largest kingdom in the sub-continent, where a highly sophisticated people traded gold and ivory with China, India and Egypt. The region had a population of more than 5 000 inhabitants.
With the advent of radiocarbon dating in the 1950's, it was discovered that nearby Bambandyanalo had been settled 300 years before Mapangubwe, in about 1000 AD, and that its people had been in continuous occupation for 200 years. Archeologists also uncovered human burials that contained glass beads and copper bracelets along with profusely decorated pottery bowls, pots and beakers. Animal burials consisting of skulls or jawbones also contained copper ornaments, seashells and pottery fragments.
The Moloko Pottery of the Later Iron Age was banded and stamped decorated, with tapered or out-turned rims, and occurs mainly at sites between the Witwatersrand and the Magaliesberg. Phalaborwa pottery shows little change in 400 years and bears simple, cut designs originally produced by Venda speaking people, even up till today.
For more than 800 years later the Iron Age was one of stability in South Africa. People learnt to spin and weave fibers into cloth, to twist and plait ropes, and there was a greater reliance on domestic livestock as a source of meat. Millets, cotton and sorghum were the staple crops, supplemented by maize after contact with Portuguese traders. Trade with the Mozambique coast increased dramatically during the Later Iron Age.
The only question left for all to answer is how come a highly civilized nation that traded in peace and harmony with Arab, Chinese and Indian traders lost everything they had? The answer might be with South African universities that has a rich collection of artifacts?
Recent excavations revealed a court sheltered in a natural amphitheatre at the bottom of the hill, with an elite graveyard at the top. The investigations and research continue.
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History of Lesotho
From Wikipedia, the free encyclopedia
Jump to: navigation, search
Flag of Lesotho
The area now known as Lesotho /lɪˈst/ goes back as many as 40,000 years. The present Lesotho (then called Basutoland) emerged as a single polity under paramount chief Moshoeshoe I in 1822. Under Mashoeshoe I, Basutoland joined other tribes in their struggle against the Lifaqane associated with the reign of Shaka Zulu from 1818 to 1828.
Ancient history[edit]
At some stage during their migration south from a tertiary dispersal area Bantu speaking peoples came to settle the lands that now make up Lesotho as well as a more extensive territory of fertile lands that surround modern day Lesotho. These people spoke a unique "South Sotho" dialect seSotho and called themselves the Basotho. There were several severe disruptions to the Basotho peoples in the early 19th century. Firstly marauding Zulu clans, displaced from Zululand as part of the Lifaqane (or Mfecane), wrought havoc on the Basotho peoples they encountered as they moved first west and then north. Secondly no sooner than the Zulu has passed to the north than the first Voortrekkers arrived, some of whom obtained hospitality during their difficult trek north. Early Voortrekker accounts describe how the lands surrounding the mountain retreat of the Basotho had been burnt and destroyed, in effect leaving a vacuum that subsequent Voortrekkers began to occupy.
However, this interpretation of history for the entire southern region of Africa has been refuted by Norman Etherington in The Great Treks: The Transformation of Southern Africa, 1815-1854 (Longman, 2001). Etherington argues that no such thing as the Mfecane occurred, the Zulu were no more marauding than any other group in the region, and the land the Voortrekkers saw as empty was not settled by either Zulu or Basotho because those people did not value open lowland plains as pasture.This state has been colonization of many many European states.
South Africa, Lesotho and Swazuiland in 1885.
In 1818, Moshoeshoe I /mɵˈʃwʃw/ consolidated various Basotho groupings and became their King. During Moshoeshoe's reign (1823-1870), a series of wars (1856–68) were fought with the Boers who had settled in traditional Basotho lands. These wars resulted in the extensive loss of land, now known as the "Lost Territory".
A treaty had been signed with the Boer of Griqualand in 1843 and an agreement made with the British in 1853 following a minor war. However, the disputes with the Boer over land were revived in 1858 and more seriously in 1865. The Boer had a number of military successes, killing possibly 1,500 Basotho soldiers, and annexed an expanse of arable land which they were able to retain following a treaty at Thaba Bosiu. In order to protect his people, Moshoeshoe appealed to the British for assistance, and in March 1868 the land was placed under British protection and the Boer were ordered to leave. A treaty was signed at Aliwal in 1869 between the British and the Boer defining the boundaries of the protectorate, the arable land west of the Caledon River remained in Boer hands and is referred to as the Lost or Conquered Territory. Moshoeshoe died in 1870.
In 1871 the protectorate was annexed to Cape Colony. The Basotho resisted the British and in 1879 a southern chief, Moorosi, rose in revolt. The rising was crushed and Moorosi was killed in the fighting. The Basotho then began to fight amongst themselves over the division of Moorosi's lands. The British extended the Cape Peace Preservation Act of 1878 to cover Basutoland and attempted to disarm the natives. Much of the colony rose in revolt in the Gun War (1880-1881), inflicting significant casualties upon the colonial British forces sent to subdue it. An 1881 peace treaty failed to quell sporadic fighting.
Cape Town's inability to control the territory led to its return to crown control in 1884 as the Territory of Basutoland. The colony was bound by the Orange River Colony, Natal Colony, and Cape Colony it was divided into seven administrative districts - Berea, Leribe, Maseru, Mohales Hock, Mafeteng, Qacha's Nek and Quthing. The colony was ruled by the British Resident Commissioner, who worked through the pitso (national assembly) of hereditary native chiefs under one paramount chief. Each chief ruled a ward within the territory. The first paramount chief was Lerothodi, the son of Moshoeshoe. During the Second Boer War the colony was neutral. The population was around 125,000 (1875), 310,000 (1901) and 349,000 (1904).
The differing fates of the seSotho-speaking peoples in the Protectorate of Basotholand and in the lands that became the Orange Free State are worth noting. The Orange Free State became a Boer-ruled territory. However at the end of the Boer War it was colonised by the British, and this colony was subsequently incorporated by Britain into the Union of South Africa as one of four provinces. It is still part of the modern day Republic of South Africa, now known as the Free State. In contrast Basotholand, along with the two other British Protectorates in the sub-Saharan region (Bechuanaland and Swaziland), was precluded from incorporation into the Union of South Africa. These protectorates were individually brought to independence by Britain in the 1960s in line with the trend towards self-government and independence that swept the British Empire following the close of the Second World War, a trend that reached its peak in Africa in the late 1950s and early 1960s. By becoming a protectorate Basotholand and its inhabitants were not subjected to Afrikaner rule, which saved them from experiencing Apartheid, and so generally prospered under more benevolent British rule. Basotho resident in Basotholand had access to better health services and to education, and came to experience greater political emancipation through independence. These lands protected by the British, however, had a much smaller capacity to generate income and wealth than the "lost territory" had, which had been granted to the Boers.
After a 1955 request by the Basutoland Council to legislate its internal affairs, in 1959 a new constitution gave Basutoland its first elected legislature. This was followed in April 1965 with general legislative elections with universal adult suffrage in which the Basotho National Party (BNP) won 31 and the Basutoland Congress Party (BCP) won 25 of the 65 seats contested.
Kingdom of Lesotho[edit]
On October 4, 1966, the Kingdom of Lesotho attained full independence, governed by a constitutional monarchy with a bicameral Parliament consisting of a Senate and an elected National Assembly. Early results of the first post-independence elections in January 1970 indicated that the BNP might lose control. Under the leadership of Prime Minister Chief Leabua Jonathan, the ruling Basotho National Party (BNP) refused to cede power to the rival Basotholand Congress Party (BCP), although the BCP was widely believed to have won the elections. Citing election irregularities, Prime Minister Leabua Jonathan nullified the elections, declared a national state of emergency, suspended the constitution, and dissolved the Parliament. In 1973, an appointed Interim National Assembly was established. With an overwhelming progovernment majority, it was largely the instrument of the BNP, led by Prime Minister Jonathan. In addition to the Jonathan regime's alienation of Basotho powerbrokers and the local population, South Africa had virtually closed the country's land borders because of Lesotho support of cross-border operations of the African National Congress (ANC). Moreover, South Africa publicly threatened to pursue more direct action against Lesotho if the Jonathan government did not root out the ANC presence in the country. This internal and external opposition to the government combined to produce violence and internal disorder in Lesotho that eventually led to a military takeover in 1986.
Under a January 1986 Military Council decree, state executive and legislative powers were transferred to the King who was to act on the advice of the Military Council, a self-appointed group of leaders of the Royal Lesotho Defense Force (RLDF). A military government chaired by Justin Lekhanya ruled Lesotho in coordination with King Moshoeshoe II and a civilian cabinet appointed by the King.
In February 1990, King Moshoeshoe II was stripped of his executive and legislative powers and exiled by Lekhanya, and the Council of Ministers was purged. Lekhanya accused those involved of undermining discipline within the armed forces, subverting existing authority, and causing an impasse on foreign policy that had been damaging to Lesotho's image abroad. Lekhanya announced the establishment of the National Constituent Assembly to formulate a new constitution for Lesotho with the aim of returning the country to democratic, civilian rule by June 1992. Before this transition, however, Lekhanya was ousted in 1991 by a mutiny of junior army officers that left Phisoane Ramaema as Chairman of the Military Council.
Because Moshoeshoe II initially refused to return to Lesotho under the new rules of the government in which the King was endowed only with ceremonial powers, Moshoeshoe's son was installed as King Letsie III. In 1992, Moshoeshoe II returned to Lesotho as a regular citizen until 1995 when King Letsie abdicated the throne in favor of his father. After Moshoeshoe II died in a car accident in 1996, King Letsie III ascended to the throne again.
In 1993, a new constitution was implemented leaving the King without any executive authority and proscribing him from engaging in political affairs. Multiparty elections were then held in which the BCP ascended to power with a landslide victory. Prime Minister Ntsu Mokhehle headed the new BCP government that had gained every seat in the 65-member National Assembly. In early 1994, political instability increased as first the army, followed by the police and prisons services, engaged in mutinies. In August 1994, King Letsie III, in collaboration with some members of the military, staged a coup, suspended Parliament, and appointed a ruling council. As a result of domestic and international pressures, however, the constitutionally elected government was restored within a month.
In 1995, there were isolated incidents of unrest, including a police strike in May to demand higher wages. For the most part, however, there were no serious challenges to Lesotho's constitutional order in the 1995-96 period. In January 1997, armed soldiers put down a violent police mutiny and arrested the mutineers.
In 1997, tension within the BCP leadership caused a split in which Dr. Mokhehle abandoned the BCP and established the Lesotho Congress for Democracy (LCD) followed by two-thirds of the parliament. This move allowed Mokhehle to remain as Prime Minister and leader of a new ruling party, while relegating the BCP to opposition status. The remaining members of the BCP refused to accept their new status as the opposition party and ceased attending sessions. Multiparty elections were again held in May 1998.
Although Mokhehle completed his term as Prime Minister, due to his failing health, he did not vie for a second term in office. The elections saw a landslide victory for the LCD, gaining 79 of the 80 seats contested in the newly expanded Parliament. As a result of the elections, Mokhehle's Deputy Prime Minister, Pakalitha Mosisili, became the new Prime Minister. The landslide electoral victory caused opposition parties to claim that there were substantial irregularities in the handling of the ballots and that the results were fraudulent. The conclusion of the Langa Commission, a commission appointed by Southern African Development Community (SADC) to investigate the electoral process, however, was consistent with the view of international observers and local courts that the outcome of the elections was not affected by these incidents. Despite the fact that the election results were found to reflect the will of the people, opposition protests in the country intensified. The protests culminated in a violent demonstration outside the royal palace in early August 1998 and in an unprecedented level of violence, looting, casualties, and destruction of property. In early September, junior members of the armed services mutinied. The Government of Lesotho requested that a SADC task force intervene to prevent a military coup and restore stability to the country. To this end, Operation Boleas, consisting of South African and (later) Botswana troops, entered Lesotho on September 22, 1998 to put down the mutiny and restore the democratically elected government. The army mutineers were brought before a court-martial.
After stability returned to Lesotho, the SADC task force withdrew from the country in May 1999, leaving only a small task force (joined by Zimbabwean troops) to provide training to the LDF. In the meantime, an Interim Political Authority (IPA), charged with reviewing the electoral structure in the country, was created in December 1998 and devised a proportional electoral system to ensure that there be opposition in the National Assembly. The new system retained the existing 80 elected Assembly seats, but added 40 seats to be filled on a proportional basis. Elections were held under this new system in May 2002, and the LCD won again, gaining 54% of the vote. For the first time, however, opposition political parties won significant numbers of seats, and despite some irregularities and threats of violence from Major General Lekhanya, Lesotho experienced its first peaceful election. Nine opposition parties now hold all 40 of the proportional seats, with the BNP having the largest share (21). The LCD has 79 of the 80 constituency-based seats.
See also[edit]
• Etherington, Norman. The Great Treks: The Transformation of Southern Africa, 1815-1854. Harlow, England: Longman. ISBN 0-582-31567-0. OCLC 47893949.
External links[edit]
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Madden Julian Oscillation
The Madden Julian Oscillation (MJO), or 40 day wave as it is sometimes called, was first discovered by Madden and Julian in the early 1970s. The MJO can be observed as a band of low atmospheric pressure originating off the east coast of central Africa travelling eastward across the Indian Ocean and northern Australia roughly every 30 to 60 days. Research has shown the MJO to be a useful indicator of the timing of potential rainfall events across much of tropical Australia, including parts of Queensland.
During summer/early autumn the MJO can also intensify the monsoon season as well as help trigger cyclones if there are any existing low-pressure systems in the Coral Sea. There is also the potential for it to create westerly wind bursts in the central Pacific after it has passed over Australia. From late summer through to late winter westerly wind bursts in the Pacific can help trigger an El Nino event.
Tracking and using the MJO
It is important to realise that all methods of tracking or forecasting the MJO are still experimental.
Bureau of Meteorology
This method we are going to show you has been developed by Matthew Wheeler from the Bureau of Meteorology Research Centre and it lets you view the passage of the MJO as it propagates along the equator.
An example of the MJO over a 40 day period is as follows:
Graph of MJO over a 40 day period
The diagram is split into 8 sections, or "phases". These phases represent the different location of the MJO as it moves along the equator. The cycle usually starts on the east coast of central Africa (Phases 8 and 1). From there the MJO passes through the Indian Ocean (Phases 2 and 3), across the top of Australia (Phases 4 and 5) and through the Pacific Ocean (Phases 6 and 7). The influence on Australian rainfall is different depending on the location of the MJO in each phase.
The coloured lines on the diagram represent the passage of the MJO. The green line represents the passage of the MJO through April and the blue line represents its passage through May. The numbered dots along each line represent the days of each month.
If the MJO is inside of the circle, which is in the centre of the diagram, the MJO is classed as 'weak' while the further out it is from the circle the 'stronger' the MJO cycle is. Generally, the influence of the MJO is greater when it is stronger. When it is 'weak', it should not be used as a forecasting guide.
Further information
Further information on westerly wind bursts
Last updated 06 April 2009
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You don’t need magic. But you do need to understand some basic science.
You’ll need:
• A penny.
• A piece of paper.
• A clear water glass.
• A saucer.
Put the penny on the paper and cover it with a clear glass filled with water. Can your child see the penny? Where’s the best place to see it?
Now cover the glass with the saucer. Can your child find the penny without looking straight down through the water glass? What happened to make the penny disappear?
We can see objects because light rays reflect off them into our eyes. But every time light hits an object of a different density, it bends a little. So the light reflecting off the penny has to pass through air, water and glass. Each has a different density. By the time that light ray gets to your eyes, it looks like the penny is someplace it’s not.
Copyright © Parent Institute
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Thousand Islands National Park of Canada
Frontenac Arch Biosphere Reserve
A biosphere reserve, as defined by the United Nations Educational, Scientific and Cultural Organization (UNESCO), is an area that has important natural and ecological values and is a place where people live, work, and enjoy a variety of economic and recreational activities based on respect for the environment. The concept of a biosphere reserve is that local committees of representatives from key sectors such as agriculture, tourism, business, conservation, and education, work together to develop projects that link conservation with economic development in their region. The committees are voluntary and community-based, not connected to governmental or regulatory authorities.
As of July 2005, UNESCO had designated 482 biosphere reserves in 102 countries around the world. Thirteen have been designated in Canada, including the Frontenac Arch Biosphere Reserve, which was officially recognized in 2002. The Frontenac Arch Biosphere Reserve complements other local and regional conservation initiatives and is a coordinating force to reduce duplication of effort. It also adds the new dimension of linking conservation and economic development. Celebrating the historical and cultural richness of the area's past, the reserve works to sustain its future with shoreline and water quality conservation measures combined with tourism and recreational development.
Canadian Biosphere Reserves:
Charlevoix (Québec)
Clayoquot Sound (British Columbia)
Frontenac Arch (Ontario)
Georgian Bay Littoral (Ontario)
Lac St. Pierre (Québec)
Long Point (Ontario)
Mont Saint Hilaire (Québec)
Mount Arrowsmith (British Columbia)
Niagara Escarpment (Ontario)
Redberry Lake (Saskatchewan)
Riding Mountain (Manitoba)
Southwest Nova (Nova Scotia)
Waterton (Alberta)
For more information check out the UNESCO website
Frontenac Arch Biosphere Reserve Map
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Logo of pnasPNASInfo for AuthorsSubscriptionsAboutThis Article
Proc Natl Acad Sci U S A. Aug 10, 2010; 107(32): 14269–14273.
Published online Jul 23, 2010. doi: 10.1073/pnas.1005338107
PMCID: PMC2922565
Among the fundamental questions regarding cultivated plants is their geographic origin and region of domestication. The genus Cucumis, which includes cucumber (Cucumis sativus) and melon (Cucumis melo), has numerous wild African species, and it has therefore been assumed that melon originated in Africa. For cucumber, this seemed less likely because wild cucumbers exist in India and a closely related species lives in the Eastern Himalayas. Using DNA sequences from plastid and nuclear markers for some 100 Cucumis accessions from Africa, Australia, and Asia, we show here that melon and cucumber are of Asian origin and have numerous previously overlooked species-level relatives in Australia and around the Indian Ocean. The wild progenitor of C. melo occurs in India, and our data confirm that the Southeast Asian Cucumis hystrix is the closest relative of cucumber. Most surprisingly, the closest relative of melon is Cucumis picrocarpus from Australia. C. melo diverged from this Australian sister species approximately 3 Ma, and both diverged from the remaining Asian/Australian species approximately 10 Ma. The Asian/Australian Cucumis clade comprises at least 25 species, nine of them new to science, and diverged from its African relatives in the Miocene, approximately 12 Ma. Range reconstruction under maximum likelihood suggests Asia as the ancestral area for the most recent common ancestor of melon and cucumber, fitting with both having progenitor populations in the Himalayan region and high genetic diversity of C. melo landraces in India and China. Future investigations of wild species related to melon and cucumber should concentrate on Asia and Australia.
Keywords: ancestral areas, crops, economic plants, wild progenitors
Among the most fundamental and debated questions regarding the evolution of cultivated plants is their geographic origin and region of domestication (1). Recent phylogeographic and phylogenetic work on cassava, pumpkin, corn, potato, and rice (26) has uncovered the likely places of origin and domestication of these crops. Although many premolecular hypotheses about the domestication of particular species still require testing, it is clear that the Indo-Chinese region has produced a particularly long list of crops. These include rice (Oryza sativa), millets (Setaria spp.), beans (Vigna mungo; Vigna radiata), angled loofah (Luffa acutangula), yams (Dioscorea spp.), and taro (Colocasia esculenta) (79). Archaeological evidence from northern India documents these Neolithic crops from 7,000 BC onward, and by the early second millennium, there is evidence of Western crops arriving in India through trade, such as wheat, barley, lentils, grasspea, and peas (7).
One of the crops domesticated in the Indo-Gangetic plain is cucumber, Cucumis sativus. Evidence for this consists in the occurrence there of a wild progenitor, C. sativus var. hardwickii (10, 11) and in comparative linguistic evidence (7, 8). Fossil seeds of cucumber and melon cannot be reliably distinguished, and archeological reports therefore are of limited value for pinpointing areas of melon or cucumber domestication or identifying the routes by which these crops arrived in a particular region (12). Cucumber and melon today are among the 20 most important vegetable crops worldwide (13). The first complete genome of cucumber was released last year (14), and the genome of melon is being completed (15).
In contrast to cucumber, the geographic origin and region of domestication of melon (Cucumis melo) have remained unclear. Nineteenth-century taxonomists suggested that melon probably originated and was domesticated in Asia (e.g., ref. 11). This idea became discredited as workers began to study Cucumis chromosome numbers (16). C. sativus has a chromosome number of 2n = 14, whereas C. melo has a chromosome number of 2n = 24. At least 30 other species of Cucumis have had their chromosomes counted, all but one from Africa and all having 2n = 24 or multiples thereof (17). Based on the impressive species richness in Africa and the identical chromosome number of C. melo and African Cucumis, modern authors have held that C. melo is of African origin (1822). This view has persisted even in the face of genetic data pointing to greatest genetic diversity in Indian and East Asian landraces of C. melo (2326) and despite numerous failed attempts to produce fertile F1 offspring from crosses of C. melo and African species of Cucumis (17).
Phylogenetic studies on the genus Cucumis have been Africa-biased in terms of the included species (2729). These studies yielded contradictory results regarding the closest relatives of C. sativus and C. melo. A 2007 study (29) inferred that South African C. sagittatus is the sister species of C. melo, although this was only observed with nuclear ribosomal internal transcribed spacer (ITS) sequences, not chloroplast sequences. Other studies that also used ITS (27, 28, 30) found C. melo isolated from the other included African species and instead sister to a small clade of five Asian and one Australian species. Although not resolving the position of C. melo, these studies clarified that the genus Cucumis in its traditional circumscription (17) was paraphyletic (28, 29, 31), with species from five other genera nested inside it. [The necessary nomenclatural changes were made previously (32, 33); here we use these up-dated species names.]
Here we investigate the evolutionary relationships and geographic origin of melon and cucumber by sampling Cucumis accessions covering the entire natural range of the genus from Africa to Southeast Asia to Australia, the Pacific and the Indian Ocean islands. The geographic origin of the plants sequenced is shown in Fig. 1. We included new collections from fieldwork in Australia and Thailand as well as old material from herbaria, including type material of long synonymized names.
Fig. 1.
The natural geographic range of Cucumis (shaded) and the geographic origin of the sequenced plant material. Triangles, Asian/Australian clade comprising cucumber and melon; circles, African grade; stars, outgroup.
Knowing the progenitors and closest relatives of melon and cucumber is important because these crops are highly susceptible to drought and pathogens, including powdery mildew and several mosaic viruses (14). Besides the interest in varieties with new taste or fruit shape, there is great interest in introducing resistance genes from wild relatives. In the case of melon, the search for these relatives has so far concentrated on Africa because of the view that C. melo is of African origin (1822).
Closest Relatives of Cucumber and Melon.
A maximum likelihood phylogeny from the combined plastid and nuclear data (Fig. 2) shows that C. sativus is sister to Cucumis hystrix, confirming previous findings (2830). Cucumis setosus, an entity that the most recent monograph of Cucumis (17) synonymized under C. sativus, instead is closest to Cucumis silentvalleyi and Cucumis indicus from southern and southwestern India. Sequences of the Himalayan entities Cucumis trigonus and Cucumis callosus are nearly identical to those of C. melo (Fig. 2) and likely represent the wild progenitor of cultivated melon as these forms are fully crossable with C. melo (34). The sister species to C. melo populations is the Australian Cucumis picrocarpus, which had been synonymized under C. melo (17), but is genetically and morphologically highly distinct (Fig. 2; Fig. 3 shows a color photo of C. picrocarpus).
Fig. 2.
ML tree for 63 taxa of Cucumis (Fig. S3 shows a ML tree of all 113 accessions) based on combined sequences from chloroplast and nuclear data (6,202 aligned nucleotides; Table S1), analyzed under a GTR + Γ model. The tree is rooted on Muellerargia ...
Fig. 3.
Habits, fruits, or seeds of (A) Cucumis picrocarpus, (B) C. melo subsp. agrestis, (C) C. hystrix, (D) C. debilis, (E) C. javanicus, (F) C. costatus, (G) C. queenslandicus, (H) C. umbellatus, (I) C. ritchiei, (J) C. villosior, (K) C. sp. nov. E, and ( ...
Cucumber and melon are part of a clade that comprises 25 poorly collected and understudied species-level entities from India, Indochina, Malesia, Australia, Africa, and Indian Ocean islands (Figs. 1 and and2).2). Species recently transferred to Cucumis based on morphology (32, 33) indeed belong in the genus as indicated by chloroplast and nuclear DNA sequences (Fig. 2). Our results, however, reveal another 18 close relatives (labeled in Fig. 2) of cucumber and melon that were neither accepted in the 1993 monograph of the genus by Kirkbride (17) nor included in previous phylogenetic studies (29, 30). Nine (labeled with an upper script N in Fig. 2) represent as yet undescribed species. An important factor in the unexpected Asian/Australian diversity of Cucumis is Cucumis (Mukia) “maderaspatanus.” This polymorphic taxon, revised in 2006 (35), turns out to be a highly unnatural assembly comprising at least nine species-level entities (labeled with an upper script M in Fig. 2) that are not close to each other (Fig. 2 and Table S1). Cucumis maderaspatanus was thought to range from Africa across Asia to Australia, but accessions from these three continents do not group together.
Fruit morphology, a key trait in Cucumis breeding, differs greatly among the species of the Asian/Australian clade (Fig. 3). Early-diverging species, such as the Australian sister clade of C. javanicus and several species from India and the Eastern Himalayas (C. hystrix, C. sativus var. hardwickii, Cucumis debilis, C. setosus, C. silentvalleyi, C. indicus), have more or less ellipsoid fruits that stay green or turn yellow-orange at maturity. By contrast, the Cucumis ritchiei/C. maderaspatanus clade is characterized by smooth, round fruits that turn red at maturity.
Age of Asian/Australian Cucumis Clade and Ancestral Area Reconstruction.
A relaxed molecular clock for the Asian/Australian radiation of Cucumis, calibrated with a secondary calibration from a Cucurbitaceae clock study that used three fossil and one geological calibration (36), indicates that the lineage comprising melon and cucumber split from its African ancestor 11.9 ± 2.0 Ma ago (Fig. S1). Ancestral area reconstruction under maximum likelihood yields Asia as the area of the most recent common ancestor of melon and cucumber (Fig. S2). The split between melon and its Australian sister species, C. picrocarpus, occurred approximately 2.8 ± 1.0 Ma, and that between cucumber and its sister species C. hystrix, approximately 4.6 ± 1.4 Ma.
As per this study, Cucumis comprises some 25 Asian and Australian species (Fig. 2) in addition to its approximately 30 African species. The increase in Asian/Australian Cucumis species, compared with the 12 known in 2008 (32, 33) or the two known in 1993 (17), implies that Cucumis was much less understood than hereto thought. Few of the Asian and Australian species are in cultivation, most have never had their chromosomes counted, and little is known about their ecology and distribution. A likely reason for the lack of attention paid to Asian and Australian Cucumis is the almost dogmatic view among Cucumis specialists that the genus comprised just two Asian species-level taxa (C. hystrix and C. sativus) and that any Australian Cucumis-like plants could safely be called C. melo (17) or C. (Mukia) maderaspatanus (35).
The newly revealed Asian/Australian Cucumis radiation of 25 species completely changes the biogeography of the genus. Molecular-clock dating suggests divergence of the Asian/Australian clade from its African relatives at 11.9 ± 2.0 Ma, i.e., during a Miocene period when the African-Arabian plate joined the Asian plate, leading to a closure of the seaway that had previously separated Africa from Asia (37). The ancestor of the Asian/Australian Cucumis clade probably spread to Eurasia via this land bridge, as did numerous vertebrates (38). One species, C. prophetarum, still ranges from Africa to India and Pakistan, but based on the tree topology (Fig. 2), it dispersed to Asia independently of the ancestor of the C. sativus/C. melo clade. The seven species in Australia arose from four dispersal events into that continent, all from Southeast Asia, but at widely different times (Fig. S1).
The DNA phylogeny (Fig. 2) and ancestral area reconstruction (Fig. S2) rejects Kirkbride's (17) grouping of C. melo with the African species C. hirsutus, C. humifructus, and C. sagittatus and instead supports the view of 19th century taxonomists (11, 39) that the wild progenitor of melon would be found in India. The Himalayan entities C. callosus and C. trigonus (names often synonymized with each other and/or with C. melo) (17, 40, 41) produce fertile F1 offspring when crossed with C. melo (34) and clearly are the wild progenitor from which melon was domesticated. The melon land races occurring in South and East Asia exhibit high genetic diversity (2326, 42) and deserve to be sampled more densely in future studies. The surprising finding that an Australian species (C. picrocarpus) is the sister of the C. melo/C. callosus/C. trigonus complex underscores how little is known of the Australian Cucurbitaceae diversity. Most native Australian cucurbits have close relatives among tropical Asian and even Eurasian lineages (e.g., Austrobryonia, Diplocyclos, Neoalsomitra, Neoachmandra, Trichosanthes) and reached Australia from the north (43). It is possible that other relatives of C. melo exist in under-collected regions between India and Australia or may be hiding among unidentified or misclassified material in herbaria.
Most of the approximately 66 species of Cucumis now known are monoecious annuals, but dioecious mating systems and a perennial habit evolved several times within the genus. We have begun bringing Asian and Australian species into cultivation to study fruit morphology and chromosomes. The evolution of smooth fruits from spiny fruits (Fig. 3), a traditional key character in Cucumis, and the mode of fruit opening are much more plastic than formerly thought (see ref. 28). Overall, the loss of spines appears correlated with a round shape and red color at maturity, probably in connection with bird dispersal. This fits with the inferred dispersal from Asia to Australia, Africa, and various Indian Ocean islands of taxa in the C. ritchiei/C. maderaspatanus clade (Fig. 2).
Analyses of the synteny between C. sativus, C. melo (melon), and Citrullus lanatus (watermelon) have revealed that five of the seven chromosomes of C. sativus arose by fusions of 10 ancestral chromosomes after the split between C. sativus and C. melo (14). To more fully understand the rearrangements, it will be useful to now study the chromosomes of other species in the newly revealed Asian/Australian cucumber/melon clade. Study of these species’ karyotypes (and other biological traits) will be key in the search for new sources of genes for melon and cucumber improvement. The data on the phylogenetic and geographic relationships of melon and cucumber provided here represent a step toward redirected breeding efforts, which should concentrate on Cucumis in Asia and Australia, instead of sub-Saharan Africa. Further population sampling of C. callosus, C. melo, and C. trigonus across Asia will be necessary to assess whether melon was domesticated multiple times.
Materials and Methods
Fig. 1 shows the locations of 97 of the 113 accessions included in this study (including outgroups). We sequenced five chloroplast markers (the trnL intron, the intergenic spacers trnL-F, rpl20-rps12, and trnS-G; and the genes rbcL and matK) and the nuclear ribosomal DNA internal transcribed spacers ITS1 and ITS2, plus the intervening 5.8 S gene using standard procedures (SI Materials and Methods). The dataset comprised 6,202 aligned positions. Sequences were edited with Sequencher (version 4.7; Gene Codes) and aligned by eye by using MacClade version 4.0.8 (44). Maximum likelihood (ML) analyses and ML bootstrap searches were performed using RAxML version 7.0.4 (45) (http://phylobench.vital-it.ch/raxml-bb/). Tree-searches relied on the GTR + Γ model, with model parameters estimated over the duration of specified runs and 100 bootstrap replicates. We carried out Bayesian time estimation with an uncorrelated-rates model, using BEAST version 1.5.3 (46), with a Yule tree prior and the GTR + Γ model with six rate categories. There are no Cucumis fossils, and we therefore used a secondary calibration from a Cucurbitaceae-wide analysis that used four calibration points (36). Mixing of the Markov chain Monte Carlo (MCMC) chain was checked using Tracer version 1.5 (http://tree.bio.ed.ac.uk/software/tracer/) and convergence with AWTY (47). Final trees were edited in FigTree version 1.2.3 (http://tree.bio.ed.ac.uk/software/figtree/). Ancestral areas were inferred under maximum likelihood as implemented in Mesquite version 2.6 (http://mesquiteproject.org), using the Markov k-state one-parameter model, which assumes a single rate for all transitions between character states (geographic regions in this case). Further details on methods are provided in SI Materials and Methods.
Supplementary Material
Supporting Information:
This study was supported by a Waitt grant from the National Geographic Society (to S.S.R.). J. Maxwell helped with field observations in Thailand.
The authors declare no conflict of interest.
*This Direct Submission article had a prearranged editor.
Data deposition: The sequences reported in this paper have been deposited in the GenBank database. For a list of accession numbers, see Table S1.
This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1005338107/-/DCSupplemental.
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20. Kerje T, Grum M. The origin of melon, Cucumis melo: A review of the literature. Acta Hortic. 2000;510:34–37.
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22. Luan F, Delannay I, Staub JE. Chinese melon (Cucumis melo L.) diversity analyses provide strategies for germplasm curation, genetic improvement, and evidentiary support of domestication patterns. Euphytica. 2008;164:445–461.
23. Akashi Y, Fukuda N, Wako T, Masuda M, Kato K. Genetic variation and phylogenetic relationships in East and South Asian melons, Cucumis melo L., based on the analysis of five isozymes. Euphytica. 2002;125:385–396.
24. Tanaka K, et al. Molecular characterization of South and East Asian melon, Cucumis melo L., and the origin of group Conomon var. makuwa and var. conomon revealed by RAPD analysis. Euphytica. 2007;153:233–247.
25. Dhillon NPS, et al. Diversity among landraces of Indian snapmelon (Cucumis melo var. momordica) Genet Resour Crop Evol. 2007;54:1267–1283.
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34. Parthasarathy VA, Sambandam CN. Taxonomy of Cucumis callosus (Rottl.) Cogn., the wild melon of India. Cucurbit Genet Coop Rpt. 1989;3:66–67.
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Teaching through our historic sites
Bentonville Battlefield
Program Goals
The story of Bentonville Battlefield is a component for meeting the following NCSCS Goals for 8th Grade Social Studies:
The story of Bentonville Battlefield is a component for meeting the following National Standard for the Social Sciences:
• Standard 2: The course and character of the Civil War and its effects on the American people.
Program Objectives
1. Students should be able to describe the significance of the Battle of Bentonville as it relates to the state and to the outcome of the Civil War as a whole.
2. Students should have be able to discuss the impact of the battle on the Harper family and other civilians in the Bentonville area.
3. Students should understand and be able to discuss several important medical practices during the Civil War and how these are reflected in medical practices of today.
4. Students should be able to identify the significant generals that fought at the Battle of Bentonville and describe their strategy for the engagement.
5. Students should understand and be able to explain the differences between plantation slavery and slavery as practiced by the middle class.
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Return to the Bentonville Battlefield home page
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8 Roman Ampitheatres in Britain
Roman amphitheatres are large, circular or oval open-air venues with raised seating – built by the Ancient Romans.
They were used for events such as gladiator combats, chariot races, venationes (animal slayings) and executions. About 230 Roman amphitheatres have been found across the area of the Roman Empire. Early amphitheatres date from the Republic Period, though they became more monumental during the Imperial Era.
Amphitheatres are distinguished from circuses; from hippodromes, which were usually rectangular and built mainly for racing events; and from stadia, built for athletics. But several of these terms have at times been used for one and the same venue. The word amphitheatrum means “theatre all around”, i.e., a circular theatre, as distinguished from the traditional semicircular Roman theatres.
1 : Caerleon Amphitheatre (Isca Augusta)
Credit : WikiPedia
Because of its rounded form, the unexcavated amphitheatre was known to locals as ‘King Arthur’s Round Table’, but there is no known connection. An initial investigation in 1909 showed the potential for a full-scale excavation of the structure, which began in 1926 and was supervised by Victor Erle Nash-Williams.
This revealed, among other things, that the amphitheatre had been built around AD 90, but had twice been partially reconstructed, once in the early part of the 2nd century, and again about a hundred years later. The arena is oval in shape, with eight entrances, and the stadium is thought to have had a capacity of around six thousand spectators.
2 : Silchester Ampitheatre (Calleva Atrebatum)
Silchesters ampitheatre was build between AD 50 and 70 at the eastern side of the town and is one of the earliest known ampitheatres in Britain. The ampitheatre has an elliptical plan layout with two entrances on opposing sides and measures in total around 45 x 39 metres.
Credit : WikiPedia
Credit : WikiPedia
A study of the site has shown that the seating banks were constructed from soil excavated from the main arena area which lies two metres beneath the original ground level. The seating banks could hold between 4500 and 7500 spectators. It was finally abandoned in the 5th to 7th century, which is unusually late compared to other deserted Roman settlements.
3 : Carmarthen Ampitheatre (Moridunum)
Moridunum (or, almost certainly, Moridunum Demetarum) was a Roman fort and town in the Roman province of Britannia. Today it is known as Carmarthen, located in the Welsh county of Carmarthenshire (formerly in the county of Dyfed).
Credit : WikiPedia
East of the old town is one of only seven surviving Roman amphitheatres in the United Kingdom. It has the only above-ground Roman remains in the town, and was excavated in 1968. The arena itself is 46 by 27 meters. The circumference of the cavea seating area is 92 by 67 meters. It had stone walls and wooden seating and was much larger than would be expected for the size of the town.
4 : Chester Amphitheatre (Deva Victrix)
Chester Amphitheatre is a Roman amphitheatre in Chester, Cheshire. The ruins currently exposed are those of a large stone amphitheatre, similar to those found in Continental Europe, and although it was long believed that a smaller wooden amphitheatre existed on the site beforehand, excavations since 1999 have shown that the wooden grillage is the base of the seating. Today, only the northern half of the structure is exposed; the southern half is covered by buildings, some of which are themselves listed.
Credit : WikiPedia
In use through much of the Roman occupation of Britain, the amphitheatre fell into disuse around the year 350. The amphitheatre was only rediscovered in 1929, when one of the pit walls was discovered during construction work. Between 2000 and 2006, excavation of the amphitheatre took place for Chester City Council and, after 2004, English Heritage.
5 : Maumbury Rings (Durnovaria)
Maumbury Rings is a Neolithic henge in the south of Dorchester town in Dorset, England. It is a large circular earthwork, 85 metres in diameter, with a single bank and internal ditch and an entrance to the north east. The ditch was created by digging a series of funnel-shaped shafts, each 10 metres deep, which were so closely positioned as to create a continuous trench. Human and deer skull fragments were found in the ditch fill when it was excavated in the early 20th century.
Credit : WikiPedia
Two thousand five hundred years after construction, during the Roman occupation (about 100AD), the site was adapted as an amphitheatre for the use of the citizens of the nearby Roman town of Durnovaria (Dorchester). The entrance was retained and an inner enclosure built in the south west interpreted as being for the use of the performers. The inside of the henge was lowered, with the material produced piled onto the banks.
6 : Cirencester Roman Amphitheatre (Corinium Dobunnorum)
Cirencester Amphitheatre was a Roman amphitheatre located in Cirencester, Gloucestershire, England. Archeological digs have uncovered the earthworks, revealing the outline of the construction, which is still visible, with the banking reaching 25 feet from the bottom of the arena. The arena itself is approximately 150 feet (46 m) by 135 feet (41 m). Roman artefacts including coins and pottery have been discovered on the site. It is estimated that it was constructed towards the beginning of the 2nd century.
Credit : WikiPedia
Credit : WikiPedia
The earthworks show evidence of tiered wooden seats for around 8000 people, placed upon terraces made of stone.There are two entrances, located at the North-Eastern and South-Western ends of the stadium.
During the 5th century, when the Western Roman Empire was under attack and soldiers returned to Rome to defend it, the amphitheatre was fortified to defend against the invading Saxons. Wooden structures were erected within the arena itself, placed in postholes, and a portion of the North-Eastern entrance was blocked.
7 : London Roman Ampitheatre (Londinium)
The Londinium ampitheatre was constructed with stone walls that supported a timber framework of tiered seating, built initially around AD70. Upgraded in AD120 with ragstone walls the ampitheatre could hold between 6000-7000 spectators.
Credit : Billy Abbott
Credit : Billy Abbott
Discovered during expansion excavations of the Guidhall Art Gallery, the site is now visible in an underground chamber beneath street level. The size of the ampitheatre is evident on the surface, where a ring marks the circumference of the overall structure in the forecourt entrance-way to Guidhall.
The ampitheatre was abandoned in the 4th century, where it became a derelict rubbish dump during the late roman period.
8 : St Albans Roman “Theatre” (Verulamium)
Although not actually an ampitheatre, the Roman Theatre of Verulanium is certainly of worthy note. Unique in Britain, it survives as one of the only known examples of a roman theatre from Roman Britannia and is one of the most impressive roman ruins in England.
Credit : WikiPedia
Credit : WikiPedia
The theatre was built around 140AD, with a raised wooden platform for religious processions, dancing, wrestling and wild beast shows. In its prime, the theatre could seat almost 2000 spectators but was abandoned when occupation by the Romans ended between 400 and 450.
Contributing Sources : WikiPedia
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@adrianmurdoch Or even Tomen-y-Mur. I suspect infelicitous phraseology. They meant ones that could easily be seen, but then ran out at 7!
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The study of peace also involves the causes for its absence or loss. These potential causes include: insecurity, social injustice, economic inequality, political and religious radicalism, and acute racism and nationalism. From the Anglo-Norman pas , and meaning “freedom from civil disorder”, the English word came into use in various personal greetings from c.1300 as a translation of the biblical terms pax (from the Vulgate) and Greek eirene, which in turn were renderings of the Hebrew shalom.
Shalom, cognate with the Arabic “salaam”, has multiple meanings: safety, welfare, prosperity, security, fortune, friendliness. The personalized meaning is reflected in a nonviolent lifestyle, which also describes a relationship between any people characterized by respect, justice and goodwill. This latter understanding of peace can also pertain to an individual’s sense of himself or herself, as to be “at peace” with one’s own mind attested in Europe from c.1200. The early English term is also used in the sense of “quiet“, reflecting a calm, serene, and meditative approach to the family or group relationships that avoids quarreling and seeks tranquility — an absence of disturbance or agitation.
In many languages the word for peace is also used a greeting or a farewell, for example the Hawaiian word Aloha, as well as the Arabic word Salam . In English the word peace is used as a farewell, especially for the dead as in Rest In Peace, RIP.”"
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Lissajous curve
From Wikipedia, the free encyclopedia
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In mathematics, a Lissajous curve /ˈlɪsəʒ/, also known as Lissajous figure or Bowditch curve /ˈbdɪ/, is the graph of a system of parametric equations
x=A\sin(at+\delta),\quad y=B\sin(bt),
which describe complex harmonic motion. This family of curves was investigated by Nathaniel Bowditch in 1815, and later in more detail by Jules Antoine Lissajous in 1857.
The animation below shows the curve adaptation with continuously increasing \frac{a}{b} fraction from 0 to 1 in steps of 0.01. (δ=0)
Lissajous animation.gif
Below are examples of Lissajous figures with δ = π/2, an odd natural number a, an even natural number b, and |a − b| = 1.
Practical application[edit]
On an oscilloscope, we suppose x is CH1 and y is CH2, A is amplitude of CH1 and B is amplitude of CH2, a is frequency of CH1 and b is frequency of CH2, so a/b is a ratio of frequency of two channels, finally, δ is the phase shift of CH1.
A purely mechanical application of a Lissajous curve with a=1, b=2 is in the driving mechanism of the Mars Light type of oscillating beam lamps popular with rail-roads in the mid-1900s. The beam in some versions traces out a lopsided figure-8 pattern with the "8" lying on its side.
Application for the case of a = b[edit]
In this figure both input frequencies are identical, but the phase variance between them creates the shape of an ellipse.
Top: Input signal as a function of time, Middle: Output signal as a function of time. Bottom: resulting Lissajous curve when output is plotted as a function of the input. In this particular example, because the output is 90 degrees out of phase from the input, the Lissajous curve is a circle.
When the input to an LTI system is sinusoidal, the output is sinusoidal with the same frequency, but it may have a different amplitude and some phase shift. Using an oscilloscope that can plot one signal against another (as opposed to one signal against time) to plot the output of an LTI system against the input to the LTI system produces an ellipse that is a Lissajous figure for the special case of a = b. The aspect ratio of the resulting ellipse is a function of the phase shift between the input and output, with an aspect ratio of 1 (perfect circle) corresponding to a phase shift of \pm90^\circ and an aspect ratio of \infty (a line) corresponding to a phase shift of 0 or 180 degrees. The figure below summarizes how the Lissajous figure changes over different phase shifts. The phase shifts are all negative so that delay semantics can be used with a causal LTI system (note that −270 degrees is equivalent to +90 degrees). The arrows show the direction of rotation of the Lissajous figure.
Logos and other uses[edit]
See also[edit]
External links[edit]
Interactive demos[edit]
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Critical Essays
Critical Essays
(The entire section is 618 words.)
Critical Context
Zapata is one of the best-known names in twentieth century Mexican history. Popular with young readers on both sides of the Mexico-United States border, Zapata has become a romantic hero for the oppressed and a symbol of the righteous rebel. Found in many school libraries, Zapata, Mexican Rebel was written for young adults.
Syme has not tried to explain how each battle was fought during this twelve-year period of 1908 to 1920, nor has he elaborated on the personalities of the characters. By using a chronological narrative, the author has taken a complex time in Mexican history and made it accessible to his audience. Through Zapata, Mexican Rebel, Syme has successfully captured the nature of class conflict in Mexico. He has focused on Zapata, one of the men who have come to symbolize that continuing struggle. By leaving out Zapata’s personal life and concentrating on his leadership of the oppressed, Syme has not attempted to debunk Zapata as a symbol but rather has clarified that symbol. He has answered the question of what Emiliano Zapata did to be remembered. Zapata, Mexican Rebel is a valuable book for young adults who want to understand twentieth century Mexican history. For those who want to know more about Zapata and his place in history, the author has provided a limited bibliography.
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Animal Facts
Red-Rumped Agouti
Scientific Name: Dasyprocta leporina cayana
Fast Fact:
Agoutis are nervous animals always on the lookout for danger.
Red-Rumped Agouti
Red-rumped agoutis play a key role in the complex ecosystem of the forests where they live. When agoutis find extra food, they will hide their treasure for later use by burying it. While their keen sense of smell enables them to locate the hidden cache at a later time, if the nuts aren’t found, a new tree may grow. In the Amazon rainforest, the agouti is the only species responsible for reseeding the forest with Brazil nuts, a valuable export, and ensuring the growth of a new generation of trees.
STATUS: The red-rumped agouti is listed as Least Concern by the International Union for Conservation of Nature (IUCN). The population of red-rumped agoutis seems to be stable even though some of their habitats are slowly being destroyed by human interference. They are hunted by humans for pets or as meat, as well as by large mammals such as ocelots, jaguars, and coatimundis.
HABITAT: Their range extends from the northern tip of South America to the Amazon river basin and from the western borders of Venezuela and Brazil to the eastern coast of the continent. As long they have good ground cover, agoutis can live in a wide variety of habitats, but they prefer forests and areas with bodies of water and swamps. Red-rumped agoutis will rest in a burrow or hollow tree trunk where they are safe from predators. Moving their ranges seasonally based upon food availability, these creatures will spray their territory with urine to warn other agoutis to stay away.
DIET: Fallen fruit and the tender, inner kernels of nuts are the favorite foods of these terrestrial animals but they also eat leaves, roots and tubers, wood, bark, stems, seeds, grains, nectar, and flowers. Their sense of hearing is so strong that they can actually hear fruit hit the forest floor! Agoutis stand on their large hind feet and nibble food held in their forepaws.
PHYSICAL CHARACTERISTICS: Female red-rumped agoutis are larger than males. Weight ranges from about 6 to 13 pounds while the animals are approximately 19 to 25 inches long. Their fur is a speckled olive brown with a patch of long orange or red hairs on the rump. Agouti bellies are orange-brown with a white stripe down the center. The agouti has five toes on its front feet but only three on its hind feet and it walks on its toes. Their massive jaw muscles and constantly-growing incisors insure that they are able to open hard nut shells.
Social Animals
Red-rumped agoutis are fairly social and live in small family groups. It appears they mate for life. After a gestation period of 104 to 120 days, one to three precocial babies are born. Their ability to run and forage soon after birth increases their chances of survival.
Rocket Fuel
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National Afro-American League
From Wikipedia, the free encyclopedia
Jump to: navigation, search
The National Afro-American League was formed on January 25, 1890, by Timothy Thomas Fortune. Preceding the foundation of the National Association for the Advancement of Colored People (NAACP), the organization dedicated itself to racial solidarity and self-help. The organization became defunct in 1893 due to lack of support and funding.
In September 1898, Fortune presided at a meeting in Rochester, New York, called by A.M.E. Zion Bishop Alexander Walters, for the purpose of rejuvenating the League. The new organization, named the National Afro-American Council, existed until about 1908. Walters was the first president of the Council, while Fortune was the first chairman of the executive committee.
Many who originally supported the League and later, the Council, eventually started donating to the NAACP, which later became one of the most powerful anti-segregation groups.[citation needed]
See also[edit]
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What was Greek Fire?
In 672 AD, Theophanes the Confessor reported that “Kallinikos, an artificer from Heliopolis…had devised a sea fire which ignited the Arab ships and burned them with all hands. Thus it was that the Romans returned with victory and discovered the sea fire.” What was this strange Greek fire?
Greek Fire
The Roman fleet uses Greek fire against the fleet of the rebel Thomas the Slav
Attribution: Codex Skylitzes Matritensis, Bibliteca Nacional de Madrid, Vitr. 26-2, Bild-Nr. 77, f 34 v. b. (taken from Pászthory, p. 31)
Source: Wikimedia Commons
What was Greek Fire?
Greek fire was an ancient incendiary weapon of mass destruction. In the hands of the Byzantine Empire, it was a terrifying force. Greek fire differed from other similar weapons in history in four curious ways. First, it burned continuously, even underwater. Second, it consisted of a liquid substance. Third, it was propelled through the air via pressurized siphons (see picture above). And fourth, when used in battle, it was accompanied by “thunder” and “smoke.”
The exact formula for this strange weapon was a closely guarded secret and has since been lost to time. One 11th century scholar, George Kedrenos, speculated that the family of Kallinikos kept the formula a secret for centuries, even up until his time. Regardless, modern researchers speculate that possible ingredients might’ve included sulphur, naphtha, petroleum, quicklime, or phosphorous. In his article, Greek Fire: The Best Kept Secret of the Ancient World, 1LT Richard Groller makes an interesting case for petroleum.
“It is very probable then, that the basis of the earliest Greek fire was liquid rectified petroleum or volatile petrol. Petrol itself would not be very effective in flame-projectors since the projected jet dissipates too rapidly. But thickened almost to a jelly by dissolving in it resinous substances and/or sulphur the particular admixture, coupled with the mechanical means of projecting it, together constituted a great achievement of chemical engineering.” ~ 1LT Richard Groller
Guerrilla Explorer’s Analysis
Like all weapons, Greek fire had its limitations. It exhibited limited range and enemy vessels soon learned to keep their distance from it. Also, heavy winds and other conditions limited its effectiveness while causing serious safety problems for its users. Still, for a short period of time, Greek fire was the most terrifying and devastating weapon known to man.
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Designing for Stealth
X-Planes homepage
In October 2002, Boeing unveiled the Bird of Prey, a prototype that was used to demonstrate stealth features and advanced technologies that could be used on future combat aircraft. The ultra-secret project formally began in 1992, and Bird of Prey flew 38 test flights between 1996 and 1999.
How do you make an aircraft show up on a radar screen looking as small as a bird or even a large moth, and not like the lethal, 15-ton machine that it actually is? How do you prevent heat-seeking missiles from finding and destroying it?
To avoid helping potential enemies develop countermeasures, many details of stealth are classified. However, the basic principles are widely known. Select any of the categories below to find out how engineers can design planes to avoid detection.
Visual | Radar | Heat | Noise
Unlike the B-2 and F-117 in operation today, the light-gray Bird of Prey prototype was designed to be stealthy enough to operate in broad daylight. Stabilizers evenly distribute lift to minimize pressure disturbances and the moisture contrails they create. A white patch in front of the jet engine intake helps mask shadows.
While it may seem low-tech, the human eye is a powerful detector. In fact, in some circumstances a pilot may see an enemy plane before his onboard radar detector picks it up. Since the earliest days of aerial combat, planes have traditionally been painted in various types of camouflage in an attempt to blend into the natural background. Sometimes camouflage paint on the underside of an aircraft will be blue-gray, to make the plane appear to blend with the sky for anyone looking at it from below. For enemy pilots flying above, the top surface may be gray-green or gray-brown or sand-colored to match the ground (or sea) below.
In addition, designers can use brighter paint to minimize shadows cast on the plane by its own wings or other parts. They can also add specially placed lights to eliminate shadows or to illuminate the underside of a plane so it appears to those below to match the brightness of the surrounding sky. Finally, highly efficient engines can reduce smoke contrails from the engines, while moisture contrails can be diminished by inserting additives into the exhaust and by using specially designed aerodynamic surfaces to minimize pressure disturbances around the wing.
There are only six angles on the Bird of Prey, none of which is a right angle. The fuselage is rounded in order to scatter radar in many directions. The engine's air intake, a large radar target if not properly designed for stealth considerations, is on the top of the aircraft (to keep it hidden from ground-based radar) and behind the cockpit (to hide it from head-on enemy radar).
A stealthy plane's shape helps deflect echoes away from radar. Flat surfaces reflect radar most effectively, so aircraft designers avoid having any flat parts that are likely to face in the direction of threat radar on the ground or in planes up ahead. Right angles return a strong signal back to a radar detector, so these are avoided. Any angles—for example, where the wings join the fuselage—are greater or less than 90 degrees.
Radar hitting a surface such as a wing also creates electromagnetic waves that travel the length of the wing until they hit a sharp edge, or "discontinuity." At that point the waves scatter and may bounce back toward the radar detector. To send the scatter off in multiple directions and reduce the strength of the echo, edges are often saw-toothed. Saw-tooth shapes can be used throughout the plane wherever there might be discontinuities, such as along the trailing edge of a wing or at access panels or doors for landing gear or weapons.
The plane's surface can also help minimize radar echoes. Radar-absorbing materials, often made of fiberglass with carbon or ferrite particles, can be painted on or applied in composite skins. When radio waves hit these composites, much of their energy converts to heat. Sometimes designers add radar-absorbing structures beneath the skin. Honeycomb-shaped, these structures cause radar to bounce around inside the plane, dissipating energy with each bounce.
The Bird of Prey's engine intake is situated behind the cockpit, hiding its thermal signature from ground-launched missiles or thermal-imaging devices.
To avoid detection by thermal imaging devices or targeting by heat-seeking missiles, stealthy aircraft must minimize heat emissions. A major source of such infrared emissions is the engine exhaust. Engine intakes and exhausts can be mounted above the wings, lessening the chance that heat-seeking missiles shot from below will detect them. However, these masked features adversely affect aircraft maneuverability, so high-performance fighters like the F/A-22 and the X-35 JSF, which require excellent air combat capability, have their inlets and exhausts located more traditionally.
Engineers also design exhaust nozzles so that hot engine exhaust gases mix almost instantaneously with cold air surrounding the plane. Another source of heat is air friction caused by travel at very fast speeds, an effect that is particularly pronounced at the wing's leading edge. By pumping cool jet fuel inside the wing around the leading edge, this heat signature can be minimized. Sunlight glinting off the wings is another source of infrared radiation. It can be reduced through the use of IR-absorbing paints.
The Bird of Prey is a prototype stealth technology demonstrator designed mainly to avoid radar and visual detection. But it is also quieter than other fighters. Its maximum speed is only 300 miles per hour, well below the supersonic level.
Engines are an aircraft's major source of noise. Placing them on top of the airplane lessens the sound heard on the ground. In addition, great attention is paid to designing quiet engines. Traditional turbojets take a small amount of air and then shoot it out the back at very high speeds to create thrust, which is noisy. Both stealth aircraft and newer commercial planes, on the other hand, use a high bypass turbofan engine, which creates just as much if not more thrust by taking in a much higher volume of air but accelerating it less. The extra air also creates a cushion around the engine, which helps to dampen the sound. In addition, stealthy aircraft may be designed to fly only at subsonic speeds, so as to preclude the telltale sonic boom. However, higher performance stealth aircraft, like the F/A-22 and X-35, are designed to balance the tradeoffs between extreme stealth and excellent air combat performance (as measured by supersonic speed and exceptional maneuverability). These stealthy aircraft are therefore also capable of supersonic performance, and in the case of the F/A-22, of supercruise performance at very high altitudes.
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Latest Issue of Science News
Math Trek
An Attack on Fermat
Sophie Germain was the first to propose a realistic plan to prove Fermat's Last Theorem
Sponsor Message
This is part one of a two-part series. Part II: "A Mathematical Tragedy" is available at About Time.
Around 1630, Pierre de Fermat scribbled his famous note in the margin of a book stating what is now known as "Fermat's Last Theorem." "I have discovered a truly remarkable proof which this margin is too small to contain," he added. His proof has never been found and was almost certainly wrong, but Fermat's conjecture bedeviled mathematicians for centuries to come.
Mathematicians soon realized that the problem was far harder than it first appeared. Number theorists labored endlessly to nibble off small parts of it, but in the early 1800s, one mathematician finally developed a bold strategy that had the potential to solve the whole problem at once. But the entire approach was very nearly lost to history, because until recently, all the notes and manuscripts were moldering unread in a French library.
The mathematician who developed the approach was respected by luminaries like Carl Friedrich Gauss, Adrien-Marie Legendre, and Joseph-Louis Lagrange, but was marginal in the mathematical community, with no formal training or university position. That's because the mathematician was a woman—indeed, the first woman to do significant research in mathematics.
Sophie Germain has been known for her work in the theory of elasticity and the curvature of surfaces, but until now, her only known work in number theory was a single result that Legendre attributed to her in a footnote.
"What he credited to her in this footnote is in some sense really a misrepresentation of what she did," says Reinhard Laubenbacher of Virginia Polytechnic and State University in Blacksburg. He and David Pengelley of New Mexico State University in Las Cruces searched through her notes in the Bibliothèque Nationale in Paris. Of the over 2,000 pages in the archive, hundreds and hundreds concerned number theory.
Some pages contained mere doodles that degenerated into chicken scratches, but many were filled with remarkable results. Included was a 20-page manuscript Germain had written so meticulously that not a single word was scratched out. "I personally believe," Pengelley says, "that she intended to submit it to the French academy for the prize for Fermat's Last Theorem."
Fermat's Last Theorem states that there are no nonzero whole numbers x, y, and z such that xn + yn = zn for any n greater than 2. (For n = 2, there are lots of solutions, for example, 32 + 42 = 52.) No complete solution to the problem was found until 1994, when Andrew Wiles of Princeton University cracked it using very sophisticated modern techniques from algebraic geometry.
During Germain's time, the main approach to the problem was to tackle it for particular exponents n, and it was known that it would suffice to prove the theorem for prime exponents. And Germain herself used the proof she has been known for, called Sophie Germain's Theorem, to show that the theorem is true for any prime n less than 100, if none of x, y, or z is divisible by n.
This result alone was remarkable, given the challenges Germain faced. As a woman, Germain couldn't enroll in the universities in France. So she took on the identity of a male student who had recently left the school, Antoine-August LeBlanc, reading lecture notes and sending in her homework assignments.
But somehow, her instructor, the great mathematician Lagrange, discovered her secret. According to a commentator at the time, Lagrange "went to her to express his astonishment in the most flattering of terms," and the commentator goes on to say that "the appearance of this young 'geomètre' made quite a stir." Nevertheless, the barriers against Germain's inclusion in the mathematical community didn't come tumbling down. She still couldn't enroll in the university, and her education was haphazard. And even after she had produced many impressive results, she had difficulty getting access to the French Academy of Sciences.
Indeed, Pengelley and Laubenbacher believe that she must have worked in far greater isolation than previously thought, judging from her notes. Legendre had been thought to have been a mentor for Germain. They both lived in Paris and both worked on Fermat's Last Theorem. But her notes show that they independently proved many of the same theorems and seemed to know little of one another's methods.
"Legendre's techniques were much more ad hoc," Pengelley says. "Germain would develop a theoretical approach or algorithm, not a computational one. She focused on methods of general applicability. She was more the theoretical mathematician." Pengelley and Laubenbacher presented their findings at the Joint Mathematics Meetings in San Diego in January.
Furthermore, Pengelley and Laubenbacher were astonished to find that Germain had something no other mathematician had at that time: a plausible, realistic plan for cracking Fermat's Last Theorem in its entirety, not just one number at a time, and not just if none of x, y, or z is divisible by n. This newly discovered grand plan used a completely different approach than what mathematicians have known from Sophie Germain's Theorem all this time.
"She was out to prove it all in one fell swoop," Laubenbacher says. "She was going to use this new math Gauss had developed. She read Gauss's book and said, 'That's the ticket to proving Fermat!' That was very bold. Nobody thought like that. Her role in 19th-century number theory was revolutionary."
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Get the details behind our redesign
[ree-akt] /riˈækt/
verb (used with object)
to act or perform again.
1650-60; re- + act
[ree-akt] /riˈækt/
verb (used without object)
to act in response to an agent or influence:
How did the audience react to the speech?
to act reciprocally upon each other, as two things.
to act in opposition, as against some force.
to respond to a stimulus in a particular manner:
reacting to a shock by jumping; to react to the word “coward” with anger.
to undergo a chemical reaction.
1635-45; re- + act, probably modeled on Medieval Latin reagere Unabridged
Cite This Source
Examples for react
• Scientists typically respond and react after viruses have already spread.
• People react to designer labels as signals of underlying quality.
• Some people react to stress by reaching for a few too many drinks.
• The louder the call, the closer the danger-and the faster the meerkats react.
• But the teachers can change their teaching styles in order to react to different students.
• Even natural fragrances can react with ozone in the air to make toxins.
• It's the hardest known material, of course, and it doesn't react chemically with other substances.
British Dictionary definitions for react
(intransitive; foll by to, upon etc) (of a person or thing) to act in response to another person, a stimulus, etc, or (of two people or things) to act together in a certain way
(intransitive) foll by against. to act in an opposing or contrary manner
(intransitive) (physics) to exert an equal force in the opposite direction to an acting force
(chem) to undergo or cause to undergo a chemical reaction
Word Origin
C17: from Late Latin reagere, from re- + Latin agere to drive, do
(transitive) to act or perform again
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
Cite This Source
react in Medicine
react re·act (rē-ākt')
v. re·act·ed, re·act·ing, re·acts
1. To act in response to a stimulus.
2. To undergo a chemical reaction.
The American Heritage® Stedman's Medical Dictionary
Cite This Source
Word of The Day
Difficulty index for re-act
Few English speakers likely know this word
Word Value for react
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Quotes with react
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Crystal twinning
From Wikipedia, the free encyclopedia
Jump to: navigation, search
Diagram of twinned crystals of Albite. On the more perfect cleavage, which is parallel to the basal plane (P), is a system of fine striations, parallel to the second cleavage (M).
Crystal twinning occurs when two separate crystals share some of the same crystal lattice points in a symmetrical manner. The result is an intergrowth of two separate crystals in a variety of specific configurations. A twin boundary or composition surface separates the two crystals. Crystallographers classify twinned crystals by a number of twin laws. These twin laws are specific to the crystal system. The type of twinning can be a diagnostic tool in mineral identification.
Twinning can often be a problem in X-ray crystallography, as a twinned crystal does not produce a simple diffraction pattern.
Types of twinning[edit]
Quartz - Japan twin
Twinned pyrite crystal group
Simple twinned crystals may be contact twins or penetration twins. Contact twins share a single composition surface often appearing as mirror images across the boundary. Plagioclase, quartz, gypsum, and spinel often exhibit contact twinning. Merohedral twinning occurs when the lattices of the contact twins superimpose in three dimensions, such as by relative rotation of one twin from the other. An example is metazeunerite. In penetration twins the individual crystals have the appearance of passing through each other in a symmetrical manner. Orthoclase, staurolite, pyrite, and fluorite often show penetration twinning.
Galvanized surface with macroscopic crystalline features. Twin boundaries are visible as striations within each crystallite, most prominently in the bottom-left and top-right.
If several twin crystal parts are aligned by the same twin law they are referred to as multiple or repeated twins. If these multiple twins are aligned in parallel they are called polysynthetic twins. When the multiple twins are not parallel they are cyclic twins. Albite, calcite, and pyrite often show polysynthetic twinning. Closely spaced polysynthetic twinning is often observed as striations or fine parallel lines on the crystal face. Rutile, aragonite, cerussite, and chrysoberyl often exhibit cyclic twinning, typically in a radiating pattern.
Modes of formation[edit]
There are three modes of formation of twinned crystals. Growth twins are the result of an interruption or change in the lattice during formation or growth due to a possible deformation from a larger substituting ion. Annealing or transformation twins are the result of a change in crystal system during cooling as one form becomes unstable and the crystal structure must re-organize or transform into another more stable form. Deformation or gliding twins are the result of stress on the crystal after the crystal has formed. If a FCC metal like aluminum experiences extreme stresses, it will experience twinning as seen in the case of explosions. Deformation twinning is a common result of regional metamorphism.
Crystals that grow adjacent to each other may be aligned to resemble twinning. This parallel growth simply reduces system energy and is not twinning.
Twin boundaries[edit]
Fivefold twinning in a gold nanoparticle (electron microscope image).
Twin boundaries occur when two crystals of the same type intergrow, so that only a slight misorientation exists between them. It is a highly symmetrical interface, often with one crystal the mirror image of the other; also, atoms are shared by the two crystals at regular intervals. This is also a much lower-energy interface than the grain boundaries that form when crystals of arbitrary orientation grow together.
Twin boundaries are partly responsible for shock hardening and for many of the changes that occur in cold work of metals with limited slip systems or at very low temperatures. They also occur due to martensitic transformations: the motion of twin boundaries is responsible for the pseudoelastic and shape-memory behavior of nitinol, and their presence is partly responsible for the hardness due to quenching of steel. In certain types of high strength steels, very fine deformation twins act as primary obstacles against dislocation motion. These steels are referred to as 'TWIP' steels, where TWIP stands for TWinning Induced Plasticity.[1]
Deformation twins[edit]
Of the three common crystalline structures BCC, FCC, and HCP, the HCP structure is the most likely to form deformation twins when strained, because they rarely have a sufficient number of slip systems for an arbitrary shape change. High strain rates, low Stacking-fault energy and low temperatures facilitate deformation twinning.
See also[edit]
1. ^ Steinmetz, D.R.; Jäpel, T.; Wietbrock, B.; Eisenlohr, P.; Gutierrez-Urrutia, I.; Saeed (2013), Revealing the strain-hardening behavior of twinning-induced plasticity steels: Theory, simulations, experiments 61, Acta Materialia, p. 494, doi:10.1016/j.actamat.2012.09.064 .
External links[edit]
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Equipotential surface
From Wikipedia, the free encyclopedia
Jump to: navigation, search
Equipotential surfaces are surfaces of constant scalar potential. They are used to visualize an (n)-dimensional scalar potential function in (n-1) dimensional space. The gradient of the potential, denoting the direction of greatest increase, is perpendicular to the surface.
In electrostatics, the work done to move a charge from any point on the equipotential surface to any other point on the equipotential surface is zero since they are at the same potential. Furthermore, equipotential surfaces are always perpendicular to the net electric field lines passing through it.
The term is used in electrostatics, fluid mechanics, and geodesy.
See also[edit]
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Winesburg, Ohio Teaching Unit
Lesson Plans
Winesburg, Ohio Teaching Unit
Posted by prestwickhouse on August 10, 2011
Excerpt From this Document
• Imagine that you have discovered a time capsule buried by one of the residents from Winesburg, Ohio, almost one-hundred years ago. Describe what would be in the time capsule, identify which of the characters in the novel had buried it, and explain each item’s significance.
• Sherwood Anderson criticizes the ideology behind several social and cultural institutions in Winesburg, Ohio, focusing specifically on religion, marriage, and family. Select one of these institutions and describe Anderson’s assessment of the concept. Include character descriptions and actions to support your interpretation.
• Compare and contrast the George Willard at the beginning of the book with the George Willard at the end of the book. Refer to specific stories and examples.
• Study the four parts of the story “Godliness.” What commentary on religion does Anderson make in the stories? How does he make his point? Cite details from the book to support your answer.
• Identify the historical references in the novel to place the story in its correct historical context.
• Throughout the story, many townspeople share their private thoughts and experiences with George Willard. Why do you think people feel that they should confide in George?
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Subject: Literature
Contains material for: Lesson Plans
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Tapu resmi
From Wikipedia, the free encyclopedia
Jump to: navigation, search
The tapu resmi was a feudal land-registration tax in the Ottoman Empire.1
A tapu was the equivalent of a title deed for farmland, in a feudal system where farmers were proprietors rather than outright owners; this would be recorded in a tapu tahrir, a survey of land ownership and land grants which the Ottoman government used to update land-tax records, and which are now valuable to historians. Not all land was subject to the tapu system; iltizam tax-farming was more commonly applied to non-tapu land.2 A prominent 16th-century legal theorist argued that tapu resmi was contrary to shari'ah law, and was effectively a bribe; however, tapu resmi continued to be used across the Ottoman empire.3
Tapu resmi was a divani tax on these land titles, payable to the timar holder.4 Because land inherited land was subject to a change of title, tapu resmi could also be seen as an inheritance tax;5 but the tapu resmi fee was payable on other transfers too, including when farmland fell vacant because a tenant farmer died or left.6 After paying tapu resmi, a farmer would still have to pay resm-i çift (or an equivalent tax) each year.
Land which was newly brought under cultivation, such as ifrazat, would be exempt from tapu resmi until the next tahrir (survey).
In 1716, a kanunname (tax code) for the vilayet of Morea set a sliding scale of tapuu resmi fees, from 20 akçes for low-quality land to 60 akçe for high-quality land; this was categorised as a bad-i hava tax, along with adet-i deştbani.7
The tapu system was partially reformed during the tanzimat; including increased gender equality, so that women could work, or rent out, farmland;8 responsibility for collecting the tapu resmi passed to dedicated treasury officers rather than feudal lords, and documents were standardised in the 1840s.
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Motion sickness definition - Medical Dictionary definitions of popular medical terms easily defined on MedTerms
Our Motion Sickness Main Article provides a comprehensive look at the who, what, when and how of Motion Sickness
Definition of Motion sickness
Motion sickness: A disorder of the sense of balance and equilibrium and, hence, the sense of spatial orientation that is caused by repeated motion such as from the swell of the sea, the movement of a car, or the motion of a plane in turbulent air. Motion sickness is due to irritation of a portion of the inner ear called the labyrinth. The symptoms of motion sickness include nausea, vomiting, and vertigo. Other common signs of motion sickness are sweating and a general feeling of discomfort and not feeling well (malaise). Symptoms usually stop when the motion that causes it ceases. However, some people suffer symptoms for even a few days after the trip is over.
Last Editorial Review: 3/19/2012
Search MedTerms:
Back to MedTerms online medical dictionary A-Z List
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Need help identifying pills and medications?
Use the pill finder tool on RxList.
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Suggested Essay Topics
Hester in Disgrace
(Chapters 1-4)
1. Describe the narrator of the story. How does the narrator differ from a traditional first- or third-person narrator?
2. Discuss the beadle as the personification of Puritan thinking.
Hester in the Community
(Chapters 5–8)
1. Discuss the effect of the punishment upon Hester’s personality.
2. Explore the relationship of the Governor’s mansion to the “old world” and to the Puritans.
3. Examine some of the many symbols surrounding Hester Prynne, including the scarlet letter, her apparel, and her occupation.
Chillingworth and Dimmesdale
(Chapters 9–12)
1. Compare and contrast the effects of sin upon Arthur Dimmesdale and Roger Chillingworth.
2. Examine the strange relationship between Chillingworth and Dimmesdale.
3. Discuss Hawthorne’s use of coincidence and irony in these chapters.
Changes in Hester
(Chapters 13–15)
1. Discuss the Puritan moral law and the crime of independent thinking.
2. Compare Puritan parenting and Hester’s raising of Pearl.
3. How do Hester, Dimmesdale, and Chillingworth differ in their acceptance of what seems to be their fate?
Hester Attempts to Take Charge
(Chapters 16–19)
1. Compare and contrast the personalities of...
(The entire section is 288 words.)
Want to Read More?
Subscribe now to read the rest of The Scarlet Letter Critical Essays. Plus get complete access to 30,000+ study guides!
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The Linotype
What it is.
As the name implies, the Linotype is a machine that produces a solid "line of type." Introduced about 1886, it was used for generations by newspapers and general printers. It is a one-man machine: the operator sits in front with the copy to be set at the top of the keyboard. Having adjusted the machine for the required point size and line length, the metal heated to the correct temperature -- about 550 degrees Fahrenheit -- he commences setting.
A light press of the key buttons actuates a mechanism that releases the matrices. These are small pieces of brass in which the characters or dies are stamped. The matrices travel from the magazine channels where they are housed, by means of a miniature conveyor belt, into the assembler box. This assembler box is the composing stick of the Linotype. After each word the operator touches the spaceband key which allows a spaceband to fall before setting the first letter of the following word. These spacebands are steel wedges and are used to spread out the line of matrices to the required width. When these spacebands have entered the assembler they are so positioned that their minimum width is between the matrices.
When the assembler is nearly full of matrices, the operator must decide whether to send the line away for casting at the finished word; or, if the word is long and obviously will not come in the measure, just where to divide it. As these decisions are made very speedily, it is necessary for the operator to be expert in the correct dividing of words, otherwise corrections necessitating the re-setting of two or more new lines will have to be made at a later stage.
Justifying Spacebands
Having set the line of matrices and spacebands, the operator's function as regards the casting of the slug is practically finished. All that remains is for him to press a small lever and then move along to the next line.
When the operator presses the small lever at the right of the keyboard the matrices are taken automatically by the delivery carriage into the first elevator head, the latter descending to a position opposite the mold wheel through which the metal will flow. There the matrices and spacebands are justified to correct length of line. This is achieved by the justification block which pushes up the wedge-shaped spacebands until the matrices are spaced full out to measure.
The mold wheel moves forwards and the justified line of matrices forms a metal-tight joint exactly over the opening or mold in the mold wheel. Molten metal is then pumped in from the melting pot behind the mold, and the line is cast.
After the slug is cast, the mold wheel revolves, taking the mold with the slug from the horizontal casting position to the vertical ejecting position. During this movement the slug is trimmed at the foot so that it will be the correct type height.
The Linotype slug is not cast exactly to point dimensions as regards body size. On the front of the slug is a series of slightly projecting ribs. When the vertical ejecting position is reached, the slug is pushed out of the mold by means of the ejector blade, between the trimming knives, which trim the slug to an accurate body dimension, and finally the finished slug is delivered onto the galley.
But in the meantime, what of the matrices and spacebands? After the casting, they are taken first vertically by means of the first elevator and then laterally until the teeth of the matrices engage the ribs of a carrier bar attached to the second elevator lever. This lifts the line of matrices to the distributing mechanism at the top of the machine. The spacebands remain behind when the matrices are lifted to the distributor, and are brought back to their original position in the spaceband box, ready to be used again.
The distribution of the matrices to their correct channels in the magazine is one of the most interesting functions of the Linotype. The matrices have teeth in their upper ends so arranged that as they are propelled along the intermittent seven-ribbed steel distributor bar just above the open upper ends of the magazine channels, they become disengaged when over their correspoinding channels, and thereby fall into their correct places in the magazine, ready for further use.
Thus while the operator is assembling one line of matrices, a second is being cast, and a third line is being distributed back into the magazine. A magazine normally has 90 channels containing matrices, and each matrix carries two characters in any combination, although normally roman and italic are duplexed on the same matrix. Rarely used characters not contained in the magazine are inserted by hand in the assembler. After casting these are dropped off the distributor bar into a chute and finally come to rest in the "pi" box, also ready for use again.
Main | FAQ | Custom Printing | Hot-Metal Typesetting | Other Services | Woodside Press Editions | Contact Us!
Linotype | Monotype | Ludlow
Linotype Faces | Ludlow Faces | Monotype Composition Faces | Monotype Display Faces
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Biology Department
Tri-Trophic Interactions Between Plants and Insects (Spicebush, Epimecis, and Wasps)
( Volatile chemistry, rates of parasitism, and rates of herbivory vary with light environment—a case for “top-down regulation”: Tritrophic Interactions)
The purpose of this experiment is to determine if there is a relationship between the volatile chemistry (spices) of spicebush (Lindera benzoin) and the environment it is exposed to as well as the herbivory activity related specifically to the Epimecis hortaria (caterpillar).
Do the spices in Spicebush change in different habitats? Exploring the interactions taking place between organisms from different trophic levels (think “food chain!”)
• Spicebush smells “spicy.”
• We see that Spicebush gets eaten more in the shade than in the sun.
• (1) Does leaf volatile (scents and gases) chemistry of Spicebush change between (a) different light environments (sun vs. shade) and (b) different damage treatments (undamaged vs. leaf clipping vs. damage by herbivores, or caterpillars)?
• (2) Does the rate of parasitism of herbivores change in different light environments?
• If volatiles (Spicebush “spices”- scents and gases) are acting as a cue to parasitoids, then we expect: (1a) more Spicebush volatiles in sunny environments, (1b) more Spicebush volatiles with response to damage by herbivores, and (2) a higher rate of parasitism of herbivores in the sun.
• zNose portable gas chromatograph (to smell the Spicebush “spices”)
• laptop computer (to record data)
• generator (to make power for field equipment)
• sticky cards (to catch parasitoids in the sun and shade)
• caterpillars (place in the field to see if they get parasitized)
• cups (to hold caterpillars in the field)
1. Determine two field locations within Graver Arboretum. Each location must contain at least six spicebush plants growing in the sun and six spicebush plants growing in the shade.
2. Using flagging tape, mark your plants within each location, labeling with your name, date, sun or shade and a plant ID number. You will have a total of 12 plants in each location: 6 will be labeled as shade and 6 will be labeled as sun.
1. To determine light vs. shade there are two options: a) Use a light meter and determine values that fall to the higher end as sun and values to the lower as shade. b)Use your judgement, stand next to your plants and look up. If there is little to no tree (canopy) cover directly over head, consider those plants to be in sun. If there is greater than 60 % tree cover, those plants would be in the shade.
3. On each labeled plant, choose one branch at random and place a sandwich size ziplock bag over it. Zip the bag as far shut as possible without damaging the plant. (The idea behind this is to contain the odors natually emitted by the plant - small openings are ok, but try to seal as tightly as possible.) When choosing branches, try to be consistent with size, number of leaves, position on plant, leaf color, height from ground)
4. Wait ten minutes to allow plant odors to build up in the bags.
5. Take a baseline reading of the plants natural volatile compounds (odors/ chemicals) from each bagged branch using a zNose gas chromatograph and software. (It may be helpful to assess only one site per day due to sampling time)
6. Follwoing baseline readings, apply treatments to plants: the treatments will be no damage (control), mechanical damamge (clipping multiple leaves lightly on each branch), and herbivore damage (placing two epimecis caterpillar on the branch). To apply each treatment:
1. Remove ziploc bag. Lable bag with type of treatment being applied to that branch. (be sure to use the same branch that the bag came off of)
2. Of your 6 sun plants in location one, two will be no dmamge, two will be mechanical damamge and two will be herbivore damamge. This will be true of your shade plants as wellas your plants in location 2.
7. Replace ziploc bags and wait ten minutes to allow treatment to take affect.
8. Using the zNose, take volatile chemistry readings again, alternating between sun and shade, testing first the no damamge, then the mechanical damamge and finally the herbivore damage.
9. If time permits, test all treated plants a second time to gather additional data.
10. All data will have been recorded on your zNose software. Return to the lab and begin looking at your data to determine any trends.
Example of a data table
Example of a Graph
Leaf volatile chemistry graph:
This figure shows which “spices” were affected the most in different light environments and when damaged.
This figure shows which “spices” were affected the most when Spicebush was damaged by leaf clipping, damaged by herbivores, or left undamaged.
Sticky card graph:
Text Box:
This figure shows how many parasitoids of each family were present in sun or shade environments. You can see that parasitoids in the family Chalcididae were more abundant than parasitoids in the Braconidae or Ichneumonidae families.
Analysis of Data:
The data show there are differences in Spicebush’s volatile chemicals (“spices”) from the sun and shade. There was more Spice 4 produced in the sun and less C7 and C8 produced in the sun. Also, there was more C8 and C12 produced in the shade. There was also a change in volatile chemicals when Spicebush experienced leaf-clipping damage (Spice 7 and Spice 8 increased; C10 and C14 decreased) and herbivory by caterpillars (Spice 7, Spice 8, C10, and C14 all increased).
The rate of parasitism for E. hortaria was 2.2% in the sun, 6.5 % in the shade, and 9.2% overall.
Insects in the family Chalcididae were more abundant than those in Braconidae or Ichneumonidae. There was no significant difference of parasitoid abundance in sun or shade environments.
Spicebush may be attracting parasitoids with VOCs to get rid of the caterpillars, but we need further studies to confirm this. The “spice” chemicals were present in different amounts in sun and shade environments, and could help explain why caterpillars are eating more Spicebush in the shade. Parasitism of the caterpillars did not happen very often in the field.
Return to Student Project Page
Return to NSF-RET Homepage
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This is a good article. Click here for more information.
Crested auklet
From Wikipedia, the free encyclopedia
(Redirected from Crested Auklet)
Jump to: navigation, search
Crested auklet
Aethia cristatella.jpg
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Charadriiformes
Family: Alcidae
Genus: Aethia
Species: A. cristatella
Binomial name
Aethia cristatella
(Pallas, 1769)
The crested auklet was first identified in 1769 by the German zoologist Peter Simon Pallas, who named it Aethia cristatella. The genus Aethia includes four auklet species. There are no subspecies of crested auklet.[2] The family Alcidae consists of many species of shorebirds including other auklets (not in the genus Aethia), puffins, razorbills, guillemots, and murres.[3]
Crested auklets are known for their forehead crests, which is made of black forward-curving feathers. These forehead crests are highly variable, and can have between two to twenty three narrow forward curving feathers. The average auklet has 12 crest feathers, which are of variable length, between 8.1 and 58.5 millimetres.[5] Auklets have auricular plumes and a bright orange bill with curved accessory plates.[6] Like forehead crests, these features vary widely within auklet populations.[2]
Juveniles are similar to winter adults, but without auricular and crest plumes. Their bills are smaller, and colored a dull brownish yellow.[2] Juveniles take 33 days to reach adult size.[8]
Habitat and distribution[edit]
Crested auklets on a cliffside
Behavior and ecology[edit]
Breeding and parental care[edit]
The crested auklet breeding season begins mid-May and ends mid-August.[10] Their nesting sites are within the rocky crevices of North Pacific coast. They breed in dense colonies of up to one million birds. Because of this, nesting sites are in close proximity, with as little as 0.3 meters between nests. Even so, there is a high degree of territoriality, and adults show a high degree of site fidelity within a year.[11] Because mating occurs at sea and males have no copulatory organ, males must hover over females for a successful mating. Mate choice is mutual, but females do have final choice on breeding partner.[7]
Sexual selection[edit]
• The good genes hypothesis: The second mechanism is the good genes or handicap processes, where mating preference focuses on ornamental traits that reflect the health or viability of the individual expressing them. These good genes convey genetic benefits to the offspring.[14] Amotz Zahavi proposed the handicap hypothesis, where he suggests that individuals’ ornamental traits are indicators of good fitness, because they reflect the individual’s success in spite of these traits as handicaps.[14]
Visual ornaments[edit]
1838 illustration of an adult
Based on divorce rate and mortality, more than half of individuals find a new mate each year.[6] Female crest length is the primary factor of male mate switching between years.[15]
While there is variation in displays across populations, crested auklet crests and plume ornaments are consistent in expression within an individual over time. Furthermore, there is little sexual dimorphism or evidence of condition dependence. From studies, it seems to be a survival-neutral ornament.[10] Some studies, however, offer up a functional purpose for these ornaments. One study suggests a link between habitat complexity and facial feathering, where tactile facial elongation helps individuals navigate complex underground crevices.[16] The high density of crested auklet nesting sites can be expected to impose selective pressures on sensory mechanisms.[16]
Vocal ornaments[edit]
Crested auklets have a wide variety of single and complex calls. Billing is "defined as pair courtship with mutual cackling vocal display." It is a crucial part of successful pair formation and becomes harmonious once male and female partners are well acquainted.[7] Trumpet calls are one of the most common advertising calls. The call represents a complex but stereotyped vocal sequence that is linked with a specific visual display.[11] Between individuals, the calls differ in duration and frequency. Calls are primarily performed in males, but can also be seen in females. The call is particularly strong in widowed females.[7] These calls stay stable from year to year, and individuals' specific calls are associated with the maintenance of long-term social bonds between pair mates and between neighbors. This suggests that trumpet calls can be used for both short-term and long-term individual recognition. Recognition of neighboring individuals' calls is advantageous because it minimizes energy expenditure on aggressive displays, and prevents conflict between neighbors and trusted individuals (the "dear enemy phenomenon").[11]
Olfactory ornaments[edit]
Crested auklets have a distinctive citrus-like plumage odor. The scent is released when there is ruffling of feathers on the nape and upper back of the individual from threat, trumpeting, or billing displays. The cloud of scent released encourages the ruff sniff display. A ruff sniff display is when birds fully insert their half open, bill into the others' plumage. This display occurs in the absence of obvious aggression and is important for pair formation.[7] For both sexes, a strong odor attracts more individuals, which then do a ruff sniff display.[15]
Odor secretions increase during the breeding season, highlighting its association with courtship and mate selection. The scent may also act as an ectoparasite repellent.[17] This scent is also found in whiskered auklet.[8]
Conservation status[edit]
Specimen covered in oil after the MV Selendang Ayu oil spill
According to the International Union for Conservation of Nature, crested auklets are of least concern.[1] The global population is estimated to be six million individuals, while the North American population is estimated at 2.9 million birds. However, an accurate assessment of the number of birds is difficult, since those on the surface of the colony and in the nearby sea form only a small proportion of the variable and poorly understood population.[18]
1. ^ a b c BirdLife International (2012). "Aethia cristatella". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
2. ^ a b c d e f g del Hoyo, Elliot, Sargatal, Josep, Andrew, Jordi (1996). Handbook of the Birds of the World Vol. 3. Lynx Edicions. ISBN 978-84-87334-20-7.
5. ^ a b c Jones, Ian L.; Fiona M. Hunter (March 1993). "Mutual sexual selection in a monogamous seabird". Nature 362: 238–239. doi:10.1038/362238a0.
6. ^ a b Jones, Ian L.; Fiona M. Hunter (1999). "Experimental evidence for a mutual inter- and intrasexual selection favouring a crested auklet ornament". Animal Behavior 57 (3): 521–528. doi:10.1006/anbe.1998.1012.
10. ^ a b c Jones, Ian L.; Fiona M. Hunter; Gregory J. Robertson; Gail Fraser (2004). "Natural variation in the sexually selected feather ornaments of crested auklets (Aethia cristatella) does not predict future survival". Behavioral Ecology 15 (2): 332–337. doi:10.1093/beheco/arh018.
11. ^ a b c Klenova, Anna V.; Victor A. Zubakin; Elena V. Zubakina (December 2011). "Inter- and intra-season stability of vocal individual signatures in a social seabird, the crested auklet". Acta Ethol 15: 141–152. doi:10.1007/s10211-011-0120-y.
12. ^ Amundsen, Trond (April 1, 2000). "Why are female birds ornamented?". Trends in Ecology & Evolution 15 (4): 149–155. doi:10.1016/S0169-5347(99)01800-5.
13. ^ Fisher, R.A. (1915) The evolution of sexual preference. Eugenics Review 7: 184–192.
14. ^ a b Davies, Krebs, West, Nicholas B., John R., Stuart A. (2012). An Introduction to Behavioral Ecology. West Sussex, UK: Wiley-Blackwell. pp. 192–202. ISBN 978-1-4051-1416-5.
15. ^ a b Klenova, Anna V.; Victor A. Zubakin; Elena V. Zubakina (2011). "Vocal and Optical Indicators of Individual Quality in a Social Seabird, the Crested Auklet (Aethia cristatella)". Ethology 117: 356–365. doi:10.1111/j.1439-0310.2011.01880.x.
16. ^ a b Seneviratne, Sampath S.; Ian L. Jones (2010). "Origin and maintenance of mechanosensory feather ornaments". Animal Behavior 79: 637–644. doi:10.1016/j.anbehav.2009.12.010.
17. ^ Rajchard, J. (2007). "Intraspecific and interspecific chemosignals in birds: a review". Veterinarni Medicina 52 (9): 385–391.
18. ^ BirdLife International (2012) Species factsheet: Aethia cristatella. Downloaded from on 16/12/2012.
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Etiquette (礼仪)
The origins of etiquette—the conventional rules of behavior and ceremonies observed in polite society—are complex. One of them is respect for authority. From the most primitive times, subjects(臣民) showed respect for their ruler by bowing, prostrating themselves on the ground, not speaking until spoken to, and never turning their backs to the throne. Some rulers developed rules to stress even further the respect due to them. The emperors of Byzantium expected their subjects to kiss their feet. When an ambassador from abroad was introduced, he had to touch the ground before the throne with his forehead. Meanwhile the throne itself was raised in the air so that, on looking up, the ambassador saw the ruler far above him, haughty and remote.
Absolute rulers have, as a rule, made etiquette more complicated rather than simpler. The purpose is not only to make the ruler seem almost godlike, but also to protect him from familiarity, for without some such protection his life, lived inevitably in the public eye, would be intolerable. The court of Louis XIV of France provided an excellent example of a very highly developed system of etiquette. Because the king and his family were considered to belong to France, they were almost continually on show among their courtiers (朝臣). They woke, prayed, washed and dressed before crowds of courtiers. Even large crowds watched them eat their meals, and access to their palace was free to all their subjects.
Yet this public life was organized so carefully, with such a refinement of ceremonial, that the authority of the King and the respect in which he was held grew steadily throughout his lifetime. A crowd watched him dress, but only the Duke who was his first valet de chamber (贴身男仆) was allowed to hold out the right sleeve of his shirt, only the Prince who was his Grand Chamberlain could relieve him of his dressing gown, and only the Master of the Wardrobe might help him pull up his trousers. These were not familiarities, nor merely duties, but highly desired privileges. Napoleon recognized the value of ceremony to a ruler. When he became Emperor, he discarded the revolutionary custom of calling everyone "citizen", restored much of the Court ceremonial that the Revolution had destroyed, and recalled members of the nobility to instruct his new court in the old formal manners.
Rules of etiquette may prevent embarrassment and even serious disputes. The general rule of social precedence is that people of greater importance precede those of lesser importance. Before the rules of diplomatic precedence were worked out in the early sixteenth century, rival ambassadors often fought for the most honourable seating position at a ceremony. Before the principle was established that ambassadors of various countries should sign treaties in order of seniority, disputes arose as to who should sign first. The establishment of rules for such matters prevented uncertainty and disagreement, as to rules for less important occasions. For example, at an English wedding, the mother of the bridegroom should sit in the first pew or bench on the right-hand side of the church. The result is dignity and order.
Outside palace circles, the main concern of etiquette has been to make harmonious the behaviour of equals, but sometimes social classes have used etiquette as a weapon against intruders, refining their manners in order to mark themselves off from the lower classes.
In sixteenth-century Italy and eighteenth-century France, decreasing prosperity and increasing social unrest led the ruling families to try to preserve their superiority by withdrawing from the lower and middle classes behind barriers of etiquette. In a prosperous community, on the other hand, polite society soon absorbs the newly rich, and in England there has never been any shortage of books on etiquette for teaching them the manners appropriate to their new way of life.
Every code of etiquette has contained three elements: basic moral duties; practical rules which promote efficiency; and artificial, optional graces such as formal compliments to, say, women on their beauty or superiors on their generosity and importance.
In the first category are consideration for the weak and respect for age. Among the ancient Egyptians the young always stood in the presence of older people. Among the Mponguwe of Tanzania, the young men bow as they pass the huts of the elders. In England, until about a century ago, young children did not sit in their parents' presence without asking permission.
Practical rules are helpful in such ordinary occurrences of social life as
making proper introductions at parties or other functions so that people can be
brought to know each other. Before the invention of the fork, etiquette directed
that the fingers should be kept as clean as possible; before the handkerchief came
into common use, etiquette suggested that, after spitting, a person should rub the spit inconspicuously (难以察觉的) underfoot.
Extremely refined behavior, however, cultivated as an art of gracious living, has been characteristic only of societies with wealth and leisure, which admitted women as the social equals of men. After the fall of Rome, the first European society to regulate behavior in private life in accordance with a complicated code of etiquette was twelfth-century Provence, in France.
Provence had become wealthy. The lords had returned to their castles from the crusades (十字军东征) , and there the ideals of chivalry (武士制度) grew up, which emphasized the virtue and gentleness of women and demanded that a knight (骑士) should profess a pure and dedicated love to a lady who would be his inspiration, and to whom he would dedicate his brave deeds, though he would never come physically close to her. This was the introduction of the concept of romantic love, which was to influence literature for many hundreds of years and which still lives on in a belittled form in simple popular songs and cheap novels today.
In Renaissance Italy too, in the fourteenth and fifteenth centuries, a wealthy and leisured society developed an extremely complex code of manners, but the rules of behavior of fashionable society had little influence on the daily life of the lower classes. Indeed many of the rules, such as how to enter a banquet room, or how to use a sword or handkerchief for ceremonial purposes, were irrelevant to the way of life of the average working man, who spent most of his life outdoors or in his own poor hut and most probably did not have a handkerchief, certainly not a sword, to his name.
Yet the essential basis of all good manners does not vary. Consideration for the old and weak and the avoidance of harming or giving unnecessary offence to others is a feature of all societies everywhere and at all levels from the highest to the lowest. You can easily think of dozens of examples of customs and habits in your own daily life which come under this heading.
1. Etiquette simply serves the purpose of showing respect for authority.
2. Louis XIV of France made etiquette very complicated to avoid familiarity.
3. People of all societies and social ranks observe the good manners of consideration for the weak and respect for age.
4. Napoleon discarded aristocratic privileges when he became Emperor of France.
5. Etiquette has been used to distinguish people from different classes.
6. In Europe, the newly rich have added new ingredients to etiquette while they are
learning to behave appropriately for a new way of life.
7. After the sixteenth century, fights between ambassadors over precedence were a common occurrence.
8. Extremely refined behaviour had ______ on the life of the working class.
9. Basic moral duties are one of the_______of every code of etiquette.
10. According to the passage, the concept of romantic love was introduced in_______.
I. N 2. Y 3. Y 4. N 5. Y 6. NG 7. N
8. little influence 9. three elements 10. twelfth-century Provence, France
2011-04-25 09:09 编辑：甯老师
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Until the mid-eighteenth century when spinning became mechanized, cotton was an expensive and relatively unimportant textile (Virginia Postrel, “What Separates Rich Nations from Poor Nations?” New York Times, January 1, 2004). Where it used to take a hand—spinner 50,000 hours to hand-spin 100 pounds of cotton, an operator of a 1760s-era hand-operated cotton mule-spinning machine could produce 100 pounds of stronger thread in 300 hours. When the self-acting mule spinner automated the process after 1825, the time dropped to 135 hours, and cotton became and inexpensive, common cloth. In a figure, show how these technological changes affected isoquants. Explain briefly
• CreatedNovember 13, 2014
• Files Included
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50 Cards in this Set
• Front
• Back
Metal mixtures used to create improved tools and weapons is_____.
Inhabited the Tigris-Euphrates valley.
Period of time before the development of writing.
About 8,000 B.C. to 5,000 B.C. is called the______.
Neolithic Period
Earliest homo sapiens are called_____.
The oldest hominids known to manufacture tools.
Homo Habilis
Exchange of goods and ideas between people is called_____.
Cultural Diffusion
Earliest homo sapiens in Europe were_____.
Studies fossil remains to learn about prehistory.
The Old Stone Age is called the _____.
Paleolithic Period
Archaeologists would classify all of the following objects as artifacts EXCEPT...
A. Stone bed
B. Antelope skull
C. Metal blade
D. Remains of cooking pot
B. Antalope Skull
many archaeologists believe that writing developed from the record keeping of urban_____.
Many scientists dade the existence of humanlike creatures to about_____.
4.4 Million years ago
Homo erectus developed all of the following EXCEPT...
A. Ability to hunt w/ weapons
B. Ability to make barbed points
C. Ability to make clothing
D. Ability to make fire
B. The ability to make barbed points
The agricultural lifestyle led to the development of all of the following EXCEPT...
A. The Calendar
B. Rules of Inheritance
C. Land Boundries
D. Cooperative Hunting Groups
D. Cooperative Hunting Groups
The process by which people becom more proficient at earning a living by performing a single task is referred to as_____.
The specialization of labor
The loom and textile weaving were invented in the______.
Neolithic Period
The disappearance of Neanderthals was probably caused by______.
Intermarriage with homo sapiens
The Paleolithic Period is characterized by the use of______.
Stone Tools
Social standing in ancient cities can be measured by proximity to the______.
City Center
Cultural and lifestyle changes of the Neolithic Revolution were mostly caused by_____.
New agricutlural methods
The discovery of Cro-Magnons buried with daggers, proviedes evidence of______.
The existance of leaders
Astralopithecus, the earliest hominids, probably survived by____.
moving constantly in search of food
Creation myths have been found____.
in every civilization
The development of dikes, dams, and irrigation systems did all of the following EXCEPT...
A. provide a steadier flow of water
B. increase farmers' reliance on rainfall
C. ease destructive flooding
D. increase grain production
B. Increase farmers' reliance on rainfall
Lived from 1.6 million to 250,000 years ago.
Homo Erectus
Includes all humans and humanlike creatures.
Wanderers were called_____.
People living today are called____.
Homo Sapiens Sapiens
Marks and pictures representing products are_____.
Sites of Cro-Magnon cave paintings.
Study objects left behind by prehistoric people.
Land bridge between Siberia and Alaska.
Probably home of the earliest humans.
Eastern and Southern Africa
Site of the earliest cities yet discovered
Tigris-Euphrates River Valley
Which of the following were nomadic hunter-gatherers who cared for their sick and aged?
A. Neanderthals
B. Homo Habilis
C. Sumerians
D. Homo Erectus
A. Neanderthals
Bronze became a favored material for tools and weapons because_____.
It could be given a sharp edge
Complex societies with advanced knowledge of farming, trade, government and art are called_____.
All of the following are innovations of the Neolithic Revolution EXCEPT...
A. domestication of dogs and oxen
B. use of graves for burials
C. improved food storage methods
D. the development of fertilizers
B. The use of graves for burials.
Bones found at the Hadar site indicate that hominids there_____.
Could walk upright
The development of agriculture occurred_______.
At various times in different parts of the world
The exchange of ideas and goods between different groups of people is called____.
Cultural Diffusion
Radiocarbon dating involves determining the age of artifacts by______.
Measuring the amount of radioactive element remaining
All of the following valleys are sites of early urban civilizations EXCEPT...
A. Tigris-Euphrates
B. Huang He
C. Nile River
D. Neander
D. Neander
The founding of Neolithic villages such as Jericho and Catal Hujuk was made possible by____.
the development of agriculture
Land bridges that allowed migrations between places now separated by water formed during______.
The ice ages
The first homo sapiens appeared about____.
200,000 years ago
Most neanderthals lived in_____.
Small groups of 35-50 people
The remains of early homo sapiens have been found____.
on almost every continent
A people's way of life, including diet, religieous beliefs is called____.
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United States Naval Observatory
From Wikipedia, the free encyclopedia
Jump to: navigation, search
The United States Naval Observatory (USNO) is one of the oldest scientific agencies in the United States, with a primary mission[1] to produce Positioning, Navigation and Timing (PNT)[2] for the United States Navy and the United States Department of Defense. Located in Northwest Washington, D.C. at the Northwestern end of Embassy Row, it is one of the pre-1900 astronomical observatories located in an urban area; at the time of its construction, it was far from the light pollution thrown off by the (then-smaller) city center. The USNO operates the "Master Clock",[3] which provides precise time to the GPS satellite constellation run by the United States Air Force. The USNO performs radio VLBI-based positions of quasars with numerous global collaborators, in order to produce Earth Orientation parameters.
Aside from its scientific mission, a house located within the Naval Observatory complex serves as the official residence of the Vice President of the United States.
Aerial view of the U.S. Naval Observatory
President John Quincy Adams, who in 1825 signed the bill for the creation of a national observatory just before leaving presidential office, had intended for it to be called the National Observatory.[4] The names "National Observatory" and "Naval Observatory" were both used for 10 years, until a ruling was passed to officially use the latter.[5] Adams had made protracted efforts to bring astronomy to a national level at that time.[6][7] He spent many nights at the observatory, watching and charting the stars, which had always been one of Adams' avocations.
Established by the order of the United States Secretary of the Navy John Branch on 6 December 1830 as the Depot of Charts and Instruments,[8] the Observatory rose from humble beginnings. Placed under the command of Lieutenant Louis M. Goldsborough, with an annual budget of $330, its primary function was the restoration, repair, and rating of navigational instruments. It was made into a national observatory in 1842 via a federal law and a Congressional appropriation of $25,000. Lieutenant James Melville Gilliss was put in charge of "obtaining the instruments needed and books."[9] Lt. Gilliss visited the principal observatories of Europe with the mission to purchase telescopes and scientific devices and books.[10]
The observatory's primary mission was to care for the United States Navy's marine chronometers, charts, and other navigational equipment. It calibrated ships' chronometers by timing the transit of stars across the meridian. Opened in 1844 in Foggy Bottom north of the present site of the Lincoln Memorial and west of the White House (see: Old Naval Observatory), the observatory moved in 1893 to its present location[11] on a 2000-foot circle of land atop Observatory Hill overlooking Massachusetts Avenue.
In 1849 the Nautical Almanac Office (NAO) was established in Cambridge, Massachusetts as a separate organization. It was moved to Washington, D.C. in 1866, colocating with the U. S. Naval Observatory in 1893. On September 20, 1894, the NAO became a "branch" of USNO, however it remained autonomous for several years after this.[12]
Naval Observatory Flagstaff Station in Operation
In 1934, the last (then) large telescope to be installed at USNO saw "first light". This 40-inch aperture instrument[17] was also the second (and final) telescope made by famed optician, George Willis Ritchey. The Ritchey–Chrétien telescope design has since become the de facto optical design for nearly all major telescopes, including the famed Keck telescopes and the spaceborne Hubble Space Telescope. Unfortunately, light pollution forced USNO to think of other more viable locations to continue work, and so began a search. The final dark sky site chosen was Flagstaff, Arizona, and so the 40-inch telescope was moved to that location, beginning operations at the new Navy command, now called the Naval Observatory Flagstaff Station (NOFS). Those operations commenced in 1955,[18] and within a decade, the Navy's largest telescope, the 61-inch "Kaj Strand Astrometric Reflector" was built, seeing light at NOFS in 1964.[19]
The United States Naval Observatory no longer obtains significant astrometric observations, but it continues to be a major authority in the areas of Precise Time and Time Interval, Earth orientation, astrometry and celestial observation. In collaboration with many national and international scientific establishments, it determines the timing and astronomical data required for accurate navigation, astrometry, and fundamental astronomy and calculation methods — and distributes this information (such as star catalogs)[20] in the Astronomical Almanac, The Nautical Almanac, and on-line.[21]
Perhaps it is best known to the general public for its highly accurate ensemble of atomic clocks and its year 2000 time ball replacement.[22] The site also houses the largest astronomy library in the United States (and the largest astrophysical periodicals collection in the world).[23] The library includes a large collection of rare, often famous, physics and astronomy books from across the past millennium.
USNO continues to maintain its dark-sky observatory, NOFS, near Flagstaff, Arizona, which also now oversees the Navy Precision Optical Interferometer.[24] The Alternate Master Clock, mentioned above, also continues to operate at Schriever Air Force Base in Colorado.
In 1990, the Orbital Mechanics Department and Astronomical Applications Department were established, and Nautical Almanac Office became a division of the Astronomical Applications Department.[12][25] The Orbital Mechanics Department operated under P. K. Seidelmann until 1994 when the department was abolished, and its functions were moved to a group within the Astronomical Applications Department.[12] In 2010, USNO's astronomical 'department' known as the Naval Observatory Flagstaff Station (NOFS) was officially made autonomous as an Echelon Five command separate from USNO, but reporting to it. In the alpine woodlands above 7,000 feet altitude outside Flagstaff, Arizona, NOFS performs its national, Celestial Reference Frame (CRF) mission under dark skies in that region.
Since 1974, and separated from auspices of the Naval Observatory, a house situated in the grounds of the observatory at Number One Observatory Circle, which was formerly the residence of its superintendent, and later the home of the Chief of Naval Operations, has been the official residence of the Vice President of the United States.[26] The Observatory is therefore subject to tight security control enforced by the Secret Service.
According to a 15 May 2009 blog posting by Newsweek's Eleanor Clift,[27] Vice President Joe Biden revealed the existence of what Clift described as a bunker-like room in the residence. The bunker is the secure, undisclosed location where former Vice President Dick Cheney remained under protection in secret after the September 11 attacks: according to Clift's report, titled "Shining Light on Cheney's Hideaway":
Time service[edit]
Atomic clock ensemble at the U.S. Naval Observatory
• +1 202 762-1401 (Washington, D.C.)
• +1 202 762-1069
• +1 719 567-6742 (Colorado Springs)
Instrument shop[edit]
The United States Naval Observatory Instrument shop has been manufacturing precise instrumentation since the early 1900s.[citation needed]
See also[edit]
6. ^ "1991JHA 22...31D". Adsabs.harvard.edu: 31. Bibcode:1991JHA....22...31D. Retrieved 2013-08-04.
7. ^ Portolano, M (2013-03-25). "John Quincy Adams's rhetorical crusade for astronomy". Isis. 91: 480–503. PMID 11143785.
8. ^ Matchette, R. B.; et al. (1995). Guide to Federal Records in the National Archives of the United States. Washington, DC: National Archives and Records Administration.
9. ^ "The James Melville Gilliss Library".
11. ^ "The new U.S. Naval Observatory, Washington". Monthly Notices of the Royal Astronomical Society. 54: 261. 1894. Bibcode:1894MNRAS..54..261.. doi:10.1093/mnras/54.4.240.
14. ^ "Telescope: Naval Observatory 26-inch Refractor".
15. ^ "The 26-inch "Great Equatorial" Refractor".
22. ^ Nemiroff, R.; Bonnell, J., eds. (1999-10-29). "The USNO Millennium Time Ball". Astronomy Picture of the Day. NASA. Retrieved 2015-12-27.
24. ^ "NPOI". Lowell Observatory.
29. ^ a b c Matsakis, Demetrios (2010-09-20), "Report from the U.S. Naval Observatory" (PDF), Civil GPS Service Interface Committee, retrieved 2010-10-31
31. ^ "Initial Evaluation of the USNO Rubidium Fountain (PDF)" (PDF). Retrieved 2010-11-17.
34. ^ "Keeping Time By Rubidium At The Naval Observatory". NPR. Retrieved 2015-03-11.
35. ^ Telephone Time
Further reading[edit]
External links[edit]
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01 November 2004
Origins of Nantucket Whaling
Yet it was the Indians of Long Island--not Nantucket--who had taught the pioneers how to whale. According to contemporary accounts, the Indians set out from the beaches of the Hamptons to pursue their prey in dugout canoes, attacking passing whales with bone harpoons that were attached by thongs to "drags" made of wooden floats or inflated deerskins, and then killing them with bows and arrows. Each canoe was crewed by six men--four oarsmen, a steersman, and a harpooner--and the procedure of the chase was the same as that followed by thousands of American whalemen for the next three hundred years.
In the beginning, the European settlers had been satisfied with cutting up carcasses that drifted ashore during storms. The arrival of one of these "drift" whales heralded a village bonanza, because whale oil burned with a much cleaner, brighter flame than tallow, even if the blubber from which the oil was rendered had been rotten. Not only did the pioneers use it themselves, but it could be sold in New York for a gratifying sum. Then, as the Long Islanders noticed the yearly migrations of right whales just a few miles offshore, and learned that the Indians had a tradition of taking their canoes out after them, they took a more entrepreneurial stance. Instead of waiting for the whales to die of natural causes, they hired Indians to go out and kill them, supplying the crews with cedar boats, iron harpoons, and lances, all of which were much more efficient than the dugout canoes, bone harpoons, and bows and arrows that had been the old tools of the trade. The carcasses were towed up to the beach, where the Indians' employers waited with knives and cutting spades to flense the blubber and then boil--or "try out"--the oil in "try-pot" cauldrons that had been set up on the sand. This was known as shore whaling. As time went by, the Indians realized they were in a strong negotiating position. Not only did they become much more expensive to hire, but there were too few of them to meet the growing demand. So the settlers were forced to take a more active role, going out in the boats themselves.
This enterprise proved so successful that in 1672 James Loper of East Hampton was invited to Nantucket to teach the Nantucketers how to whale. Other shore settlements, including Edgartown in Martha's Vineyard, also followed the Long Islanders' lead. Then, in 1712, the Nantucket whaling industry suddenly overtook the rest, after a whaleboat was blown offshore in a gale, and came up with a pod of sperm whales. The headsman, Christopher Hussey, harpooned one, and then the boat outlasted the storm by taking shelter in the smooth waters at the lee of the oily carcass. Once the tempest was over the prize was towed home, to the amazement of all, and with instant enthusiasm a fleet of single-masted craft called "sloops" was assembled and sent out.
The sloops were only about thirty tons in size and were outfitted for voyages that lasted no more than about six weeks, but it was the world's first attempt at a sperm whale fishery. As the whales were hunted farther and farther out to sea, the vessels became bigger, reaching about sixty tons, some of them schooner-rigged. Indians made up part of the crews, the Nantucket shore-fishery having developed in a similar pattern to the Long Island enterprise, and Nantucketers commanded them. Then, as available men became scarce, the Nantucket owners lobbied for Vineyard mariners to make up their crews. And so men from Martha's Vineyard could be found in increasing numbers serving on Nantucket ships. Some even reached the rank of captain.
It was not until around 1738 that the Vineyard commenced its own sperm-whaling operation, and then it was a whale man from Nantucket, Joseph Chase, who led the way, after he moved to Edgartown and took his sloop Diamond with him. Even then it was hard for him to stimulate much local interest. This was partly because Vineyard whalemen were already sailing on Nantucket ships, and partly because of the differing physical terrain of the two islands. While Martha's Vineyard was only marginally fertile, Nantucket was not fertile at all. Nantucketers were forced to find the whole of their living at sea. By the year 1775 Nantucket listed a fleet of 150 vessels with an average burthen of one hundred tons, while the Vineyard could claim just twelve.
SOURCE: In the Wake of Madness: The Murderous Voyage of the Whaleship Sharon, by Joan Druett (Algonquin Books of Chapel Hill, 2004), pp. 23-25
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Why the US Navy wanted to communicate using whale language
In the 1960s and 1970s, the US Navy researched whether they could use synthesized whale sounds for submarines to have encoded conversations across long distances underwater. Called Project COMBO, it was a fascinating attempt at biomimicry. The project's culminating experiment even attracted a pod of whales. Alas, Project COMBO ultimately failed, but it makes for a great story. From Cara Giaimo's article in Atlas Obscura:
Positioning themselves off of Catalina Island, 150 feet underwater, they blasted their squeaky, warbly codes through a transmitter. The receiver, placed at varying distances away, plucked the messages out of the noise flawlessly. Another test, in the fall, went deeper down and extended the range. In June of 1974, they sent out a real submarine, the USS Dolphin, which successfully transmitted sounds to a receiving ship—and, in a true vote of confidence, attracted a pod of pilot whales.
After these testing successes, researchers were left with a lot of work to do. Although they had the pilot whale on lock, they wanted to expand their repertoire by inventing “techniques and equipment to synthesize large whale sounds and small whale screams.” They still had to create scalable versions of their tools, including the call generator and the spectrograph-recognizer. Looking ahead, more problems loomed: the researchers figured this was a good enough idea that the Soviets would steal it, at which point American submariners would need to add another skill to their arsenal. “Fleet sonarmen must become more familiar with bioacoustic signals,” they wrote—inspiring thoughts of submarine soldiers, facing long days underwater, taking up sonic seal- and whale-watching.
Read the rest
First photo of tarantula eating a snake in the wild
(photo by Gabriela Franzoi Dri) Read the rest
Moose warms face with car exhaust
On a brisk wintry day, this clever moose decided to use a car's exhaust to get a faceful of warm air. The best part is the car owner who keeps scraping his windshield. Read the rest
Smooth chihuahua Nana has the derp game on lock
Instagrammer Edamame114 is proud biographer of Japan's derpiest superstar chihuahua Nana. Follow Nana's adventures wearing hats, going to local landmarks, and eating treats. Warning: you may make audible sounds while scrolling. Read the rest
Stabilized footage of a cow playing with a hay bale
Redditor ibru stabilized this adorable clip of a cow rolling a hay bale down a hill: "I know it wasn't really needing to be stabilized a lot but I thought it'd make a good pano-ground gif." Read the rest
Watch a young grizzly bear play with floating video cameras
Below, a young grizzly bear plays with two GoPro cameras mounted on a pontoon floating in the clear water of the Knight Inlet on the British Columbia Coast.
"The idea was to film bears diving for fish in 2-meter deep pools," wrote Newsflare member kitchinsink, who uploaded the video. "If I was in the pool they wouldn't come and dive so I needed a camera that would float 'inconspicuously!'"
(via National Geographic) Read the rest
Watch this iguana run for its life from a snake attack
Read the rest
Cute two-faced calf is oldest of its kind to survive
Meet Lucky, a two-faced calf who lives in Campbellsville, Kentucky. Lucky is just over a month old but may be the oldest animal of its kind to survive with the genetic abnormality, called diprosopus. From National Geographic:
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Hipster snake sports mustache and sunglasses
Read the rest
2016 Comedy Wildlife photo finalists announced
Wanting to see some new animal reaction pics? Swing by The Comedy Wildlife Photography Awards and be inspired by some of 2016's best. Something for every occasion. Read the rest
Adorable doggo turns 12 and gets a Big Mac to celebrate her birthday
“My dog Pip turned 12 the other day and we gave her a Big Mac to celebrate,” says IMGURian Amandazander1d.
Read the rest
Horses can communicate with people using symbols
Researchers from the Norwegian Veterinary Institute developed and tested a system for horses and people to communicate using a symbolic language. From the Daily Grail:
...Twenty three horses learned to tell trainers if they wanted to wear a blanket or not. Subjects were shown three symbols: a horizontal bar to say "I want a blanket", a blank square for "No change", and a vertical bar for "I don't need a blanket". They learned the meanings in a day or two and using them to convey if they were too warm or too cold, building the case for self-awareness...
(In the scientific paper, the researchers write that,) "When horses realized that they were able to communicate with the trainers, i.e. to signal their wishes regarding blanketing, many became very eager in the training or testing situation. Some even tried to attract the attention of the trainers prior to the test sit- uation, by vocalizing and running towards the trainers, and follow their movements. On a number of such occasions the horses were taken out and allowed to make a choice before its regular turn, and signalled that they wanted the blanket to be removed. It turned out that the horses were sweaty underneath the blanket."
"Horses can learn to use symbols to communicate their preferences" (Applied Animal Behaviour Science)
Read the rest
What animals would look like if they had eyes at the front
A creepy series of shoops by IMGURian Kiyoi from Mashable, riffing off a single uncanny Reddit shoop.
Read the rest
The Cat from Outer Space
Movie trailer for The Cat from Outer Space (1978), directed by Norman Tokar and starring Ken Berry, Sandy Duncan, Harry Morgan, and Roddy McDowall. I predict a remake in 3... 2... 1....
If you're, er, curious, you can watch it on Amazon Video: The Cat from Outer Space
Read the rest
Drowning Pool's "Bodies" covered by angry animals
Insane Cherry was good enough to create what is undoubtedly the most metal cover of "Bodies" ever recorded. Birds, goats, camels, seals, cats, and dogs all come together for this historic collaboration. Read the rest
Warning: viewing these baby animals in cute outfits may kill you
Brace yourself for a level of cuteness that could have lasting effects. Zoo Portraits by Barcelona-based Yago Partal include interesting information about each species. That cute otter could grow to 99 pounds, the heaviest of the weasel family. Read the rest
Ominous music in shark videos makes people more negative about the fish
Read the rest
More posts
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Lord of the Flies Analysis
• Lord of the Flies has often been interpreted as an allegory of the modern world, where the island represents the world, Ralph's parliament represents democratic government, and Jack's savage tribe represents autocratic government. Jack's victory over Ralph suggests that human nature eventually devolves into savagery.
• Ralph's conch is a symbol of democracy, power, and fairness. The schoolboys collectively give the conch great significance when they impose the "rule of the conch," which states that no one can speak in meetings unless he's holding the conch.
• William Golding drew the title of Lord of the Flies from Simon's name for the severed pig head, which is surrounded by flies. This title emphasizes the violence and the savagery into which the boys descend in the course of the novel.
Literary Style
Point of View
(The entire section is 752 words.)
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Anion Gap and Osmotic Gap
Written by Tim Sheppard MBBS BSc. Created 4/10/10; last updated 19/10/10
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What is an anion gap?
The anion gap is a concept that looks at the ions dissolved in the blood, and it relies on the concept that despite all of the charged particles dissolved in it, blood has a neutral charge. This means that for every positive charge, you need a negative one to balance it out. In other words, all the positive ions (cations) are theoretically paired up with negative ones (anions).
The anion gap, then, refers to the difference between the total concentration of measured cations and the total concentration of measured anions. In other words, it looks at which ions have been unable to find a partner.
How, you might ask, could that ever happen? Well, put simply, it doesn't. Every ion has to find a partner to keep the overall charge neutral. But sometimes it will look like there's more anions than cations (or vice versa). The reason for this is that we normally only measure certain cations and anions in the blood. When we find a gap, it's because there are certain ions that we haven't been looking at. Another way of thinking about the anion gap is as a way of measuring the concentration of ions in the blood that we don't normally look for.
How do you calculate the anion gap?
The anion gap is calculated by taking the total concentration of measured cations, and subtracting the total concentration of measured anions. In practice, this means the total concentration of sodium and potassium (although potassium concentration is small, and so less important), and subtracting the total concentration of bicarbonate and chloride. Put simply:
Anion gap = cations - anions
Anion gap = ([Na+] + [K+]) - ([Cl-] + [HCO3-])
Normal values are somewhere in the region of 3 to 11 mEq per litre. The reason that you have a normal value which is positive (rather than 0) is that there are normally more unmeasured anions than unmeasured cations.
How do you interpret an anion gap?
The basic thing to remember is that the overall charge of blood will always be the same - zero. The body works hard to keep that the case. In fact, it works so hard that the cations tend not to change. Even the anions don't change that much - and when one of them does change, the other one tries to compensate - so when you get a drop in bicarbonate, the chloride will often rise to make up for it. So if the anion gap is changed, it's because the unmeasured anions have changed. The anion gap may be raised, normal or low. Let's take each one in turn.
A raised anion gap means that you are measuring a higher concentration of cations than anions. Even though the anion gap is normally positive (i.e. more cations than ions), if there is a raised anion gap, this means the difference is even greater.
How does this happen? Usually, if the concentration of bicarbonate goes down, chloride goes up to make sure you've still got the same number of anions. However, if the reason that the bicarbonate concentration has dropped is because it's swapped places with another anion, chloride doesn't need to swap in - you've still got the same number of anions already. This happens commonly when you introduce a load of acid into the blood; in order to neutralize all of the spare hydrogen ions floating around, bicarbonate binds to all of them (to form carbonic acid). However, because acids are made up of a hydrogen ion and a conjugate base (which is usually an anion), the total number of anions stays the same. Because we don't measure these anions, it looks like the anion concentration has gone down. This leads to an increased anion gap. This is commonly seen in lactic acidosis or ketoacidosis, but can also be seen with several toxins, such as aspirin, cyanide and methanol.
A normal anion gap means that nothing has changed (everything is ok!) or at least that the total concentration of measured anions has not changed. This usually means that any drop in bicarbonate is due to leakage into the gut or through the kidneys, and is immediately replaced by absorbing chloride ions. The most common reason for this to occur, then, is in diarrhoea, but it can also happen if kidney damage leads to leaking of bicarbonate. The other thing which might happen is the deliberate loss of bicarbonate if there's an excess of chloride in the blood. In either circumstance, the total concentration of measured anions is unchanged, even though the proportions of each anion have.
A low anion gap is more rare; it tends to arise when there is a rise in the concentration of measured anions (rather than a drop in cations). The first reason this may happen is because of a drop in the concentration of albumin. Albumin is a negatively charged protein - an anion - and is found normally in the blood. Since it is not normally measured, it is part of the 'anion gap'. If it leaks out (e.g. nephrotic syndrome) or is not produced adequately (e.g. liver failure), chloride and bicarbonate concentrations will increase to keep the overall charge of blood at neutral. This leads to a reduced anion gap.
The second reason for a low anion gap is the development of paraproteins, a kind of immunoglobulin found in the condition multiple myeloma. These are cations, and therefore will attract more anions in to keep the charge at neutral. Since these paraproteins are unmeasured cations, if the anions which come in are measured anions (chloride or bicarbonate), then it will look like there are more anions than cations, and again there will be an decreased anion gap.
So, put simply, a raised anion gap is commonly due to excess acid, a normal anion gap is either normal, or often due to loss of bicarbonate ions, and a low anion gap is due to losing albumin or gaining paraprotein. Great!
What is an osmotic gap?
The osmotic gap is much simpler to understand than the anion gap, and probably easier to interpret - this time looking at plasma osmolarity. Like the anion gap, it is looking for the difference between what is in the blood, and what you expect to be in the blood - unlike the anion gap, it's looking particularly at there difference between the estimated osmolarity and the actual osmolarity. In other words, when you add together the things that you think are dissolved in the blood, and then look at how much is dissolved in the blood, are they the same?
If not, there must be something else that you've not been looking for which you've missed, and which is adding to the solutes which are filling the blood. This is particularly useful to know if the substance is toxic, but hasn't yet had any effects. The blood pH may be fine, there may be no signs of any alkalosis or acidosis, but an osmotic gap shows that there is something hazardous there.
Common causes of a raised osmotic gap are ethanol and methanol, but also ethylene glycol, acetone and isopropyl alcohol.
How do you calculate the osmotic gap?
One blood test that you can do is serum osmolarity. That looks at how much is dissolved in the liquid part of blood (the serum) - how much of anything. It's not just the things you're looking for, but also the things you're not. Then you subtract the estimated osmolarity or calculated osmolarity - the total of urea, glucose and two times the sodium and potassium concentrations.
The reason we double the sodium and potassium concentrations is because sodium and potassium make up most of the cations, and each cation will be paired with an anion. Doubling the sodium and potassium gives a reasonable estimate of all the ions dissolved in the serum.
The osmotic gap is therefore given by:
Osmotic gap = actual osmolarity - calculated serum osmolarity
Osmotic gap = actual osmolarity - ([urea] + [glucose] + 2 x [Na+ + K+])
A normal osmotic gap is less than 10. If it is abnormal, it will always be high (because the measured serum osmolarity will never be lower than the calculated serum osmolarity).
Further Reading
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Xiamen was founded in 1394 at the beginning of the Ming dynasty as a center of defense against coastal pirates. Its prosperity was due to its deepwater sheltered harbor, that supplanted nearby Quanzhou, the port that had been the center of the maritime trade with the Indies.
In the mid-17th century, Xiamen and Gulangyu Island became a stronghold of Zheng Chenggong, known in the West as Koxinga, a Ming loyalist who held out against the Manchu invaders until being driven to Taiwan. Born in Japan to a Chinese pirate father and a Japanese mother, Zheng became allied with holdout Ming princes in the south who hoped for a restoration. He built up a resistance force of some 7,000 junks and a mixed force of three-quarters of a million troops and pirates. In 1661 he drove the Dutch from Taiwan and set up another base there, before his death in 1662.
After the Opium Wars Xiamen became one of the first treaty ports to be opened to foreign trade and settlement following the Treaty of Nanjing in 1842. Gulangyu Island was transformed into an international settlement, where many Victorian and Neoclassical style buildings still survive. The city’s prosperity was due both to trade and to wealth sent back by Xiamen’s substantial emigrant community of overseas Chinese.
University of Xiamen:
Huaqiao University Xiamen University
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Definition - What does Thermohydrometer mean?
A Thermohydrometer is a specially designed hydrometer that is used for measuring specific gravity or the relative density of crude oil and petroleum products. There are various types of hydrometers used for measuring the specific gravity of the liquids; however, thermohydrometers are only used in the petroleum industry. This hydrometer is similar to a thermometer and consists of a cylindrical stem and a weighted bulb thus makes it float upright when used for measurement of specific gravity.
Petropedia explains Thermohydrometer
A Thermohydrometer measures the specific gravity of crude oil and petroleum products. The specific gravity here refers to API gravity. The higher the API gravity of crude oil, the lighter and sweeter it would be and thus yields large volume of valuable petroleum fractions in terms of their market price for a refinery. These valuable petroleum fractions or products are Naphtha, Gasoline, Diesel Oil, and Kerosene.
This hydrometer is made up of glass and consists of a cylindrical stem and a weighted bulb which is filled with mercury or lead shot. This helps in making it float upright. It comes with a cylindrical container called "Graduated Cylinder” in which the sample of petroleum liquid that needs to be tested for its API gravity is poured and the thermohydrometer is lowered gently into this filled container until the hydrometer floats freely. The temperature at which the tests are conducted is generally 60º F. The mercury or the lead shot rises because of this temperature and the point at which it stops corresponds to the specific gravity of the petroleum liquid.
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Chapter 1
The Gauss Rifle:
A Magnetic Linear Accelerator
gauss rifle Click on image for animated view
The photo above shows six frames of video showing the gauss rifle in action. Each frame shows 1/30th of a second. In the first frame, a steel ball starts rolling towards a magnet taped to a wooden ruler. In the second frame, a second ball can be seen speeding between the rightmost two magnets. By the third frame, the accelerator has sped up so much that the ball that is seen leaving the left side of the device is just a blur as it smashes into the target. One ball, starting at rest, has caused another ball to leave the device at a very high speed.
gauss rifle materials Click on image for larger view
The materials are simple. We need a wooden ruler that has a groove in the top in which a steel ball can roll easily. Any piece of wood or aluminum or brass with a groove will work. We chose the ruler because they are easy to find around the house or at school or at a local stationery store.
We need four magnets. Most any type will do, but the stronger the magnets are, the faster the balls will go. Here we use the super strong gold-plated neodymium-iron-boron magnets we have made available in our catalog for the other projects. They work great.
We will also need nine steel balls, with a diameter that is a close match to the height of the magnets. We use 5/8 inch diameter nickel plated steel balls from our catalog.
The only tool we will need is a sharp knife for trimming the tape.
gauss rifle first
Click on image for larger view
We start by taping the first magnet to the ruler at the 2.5 inch mark. The distance is somewhat arbitrary -- we wanted to get all four magnets on a one foot ruler. Feel free to experiment with the spacing later.
gauss rifle tape
Click on image for larger view
With the sharp knife, trim off any excess tape. Be careful, since the knife will be strongly attracted to the magnet.
gauss rifle two
Click on image for larger view
gauss rifle all
Click on image for larger view
gauss rifle ready
Click on image for larger view
How does it do that?
The kinetic energy is now transfered to the last ball, which speeds off at 4 units, to hit the target.
Another way of looking at the mechanism
But each of these balls has another ball touching it. These second balls are not at the ground state. They are each 5/8ths of an inch from a magnet. They are easier to move than the balls that are touching the magnet.
If we were to take a ball that was touching a magnet, and pull it away from the magnet until it was 5/8ths of an inch away, we would be adding energy to the ball. The ball would be pulling towards the magnet with some considerable force. We could get the energy back by letting the ball go.
After the gauss rifle has fired, the situation is different. Now each of the balls is touching a magnet. There is one ball on each side of each magnet. Each ball is in its ground state, and has given up the energy that was stored by being 5/8ths of an inch from a magnet. That energy has gone into the last ball, which uses it to destroy the target.
Speed and kinetic energy
Why a circular track will not be a perpetual motion device
I have been getting a lot of mail asking what would happen if we made the track circular. Would we get free energy? Would the balls keep accelerating forever?
I have been tempted to reply with the famous quote: "There are two kinds of people in the world -- those who understand the second law of thermodynamics, and those who don't".
However, I am not the kind of person to leave an inquiring mind unsatisfied, and it is more productive (and kind) to explain in a little more depth what is going on.
Suppose you made a circular track, and put two balls after each magnet. When the last ball is released, it encounters a magnet that has two balls at the ground state. There is no energy to be had from this magnet. The ball just bounces back.
Now suppose you had placed three balls after each magnet. When the last ball is released, it hits a ball that is 5/8ths inch from the magnet. It has not gained much momentum, because most of the momentum gained is in the last half inch as the magnet pulls much stronger on things that are closer. But the ball has enough energy from previous accelerations to release the next ball. However, that ball has less energy than the ball that caused it to release. It may have enough energy to release another ball or two, but each ball that is released has less energy than before, and eventually the chain stops.
You can show by inductive logic that no matter how many balls you stack in front of each magnet, eventually the system stops.
To estimate the losses due to heating the balls as they compress when hit, consider a plastic tube standing upright on a table. Place one steel ball at the bottom of the tube. Now drop another ball into the tube, so it hits the ball at the bottom, and bounces back up.
Now measure how high the ball bounced. If it bounces halfway back up, the losses are 50%. Perform the experiment for yourself with the balls from the Gauss Rifle. How high does your ball bounce? Send me mail with your results.
Next: Electromagnetism
Order super magnets and steel balls here.
Send mail to Simon Quellen Field via
privacy policy
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Web Results
Figures of Speech in Macbeth - Shakespeare Online
Hyperbole (Gr. hyper, over; batto, I throw) is a figure by which things are represented as being greater or less than they really are. Hyperbole is an exaggerated ...
Hyperbole | Literary Devices
Hyperbole, derived from a Greek word meaning “over-casting” is a figure of speech, which involves an ... From William Shakespeare's “Macbeth”, Act II, Scene II,.
Hyperbole Examples and Definition - Literary Devices
In fact, his lover's breath is almost surely not as sweet-smelling as a violet, yet Shakespeare's love overcomes reason. This hyperbole example gives us greater ...
What is an example of hyperbole in "Romeo and Juliet"? | Reference ...
William Shakespeare's "Romeo and Juliet" is filled with examples of hyperbole, such as when Romeo says that "[t]he brightness of [Juliet's] cheek would shame ...
Hyperbole in Hamlet | Study.com
This lesson will define and discuss hyperbole and how it is used by Hamlet in William Shakespeare's ''Hamlet'' to express his anger, sorrow, and...
Hyperbole in Macbeth | Study.com
''Macbeth,'' like all of works by William Shakespeare, includes many striking uses of figurative language. This lesson will examine several...
Hyperbole Examples - Examples Of Hyperbole - Figures Of Speech
A hyperbole is a figure of speech which uses exaggeration for emphasis and an extra effect. ... From 'Much Ado About Nothing' by William Shakespeare.
What are examples of hyperbole in Shakespeare's Othello? How is it ...
Jun 21, 2016 ... (Act III, Scene III, Lines 378-383). (Act II, Scene III, Lines 184-185) ... William Shakespeare ... How is hyperbole used in Lord of the Flies?
PlayShakespeare.com Forum: Hamlet's hyperbole . . . (1/1)
What are we to think of Hamlet, an erudite, artistic, witty, clever, and intellectually sophisticated pragmatist, who describes his father's affection for Gertrude as so ...
Examples of Hyperbole Poem
There are many examples of hyperbole poems including Homer's epic poems and the Shakespearean pentameters.
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"language_score": 0.8685934543609619,
"url": "http://www.ask.com/web?qsrc=6&o=102140&oo=102140&l=dir&gc=1&q=Hyperbole+Shakespeare"
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Mapping the body: hyoid
The hyoid is the only bone in the throat. It is also the single bone in the body that doesn't connect directly with any others, being anchored instead by ligaments and muscles. It is composed of a central portion called the body, flanked on each side by the greater and lesser cornu. If you run your finger backwards from your chin to the point where your head meets your neck and press gently, you will be able to feel the resistance of your own hyoid bone.
One of its functions is to anchor the back of the tongue while the rest is free to move. For this reason, it plays a crucial role in speech and swallowing. The hyoid also protects the fragile tissues of the larynx and pharynx.
Although the hyoid doesn't often get seriously injured, it may break after trauma to the neck. It is a macabre statistic that in a postmortem study of a group of people murdered by strangulation, one third of victims were found to have fractured hyoids.
But most head-and-neck surgeons come into contact with the hyoid bone while performing something known as a Sistrunk's operation. During embryological development, the thyroid gland starts life at the back of the tongue before finding its correct position in the neck. In some people, there is an abnormal remnant of this early journey, known as a thyroglossal duct. Cysts may develop anywhere along its course and appear as a painless lump in the mid line of the neck. Surgical removal is the best treatment and, in order to prevent recurrence, it is necessary to cut out a core of tissue running from the base of the tongue to the thyroid, including the central portion of the hyoid bone.
Gabriel Weston is a surgeon and author of Direct Red: A Surgeon's Story.
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Owner of Broca’s area identified
Broca’s area was one of the first brain areas identified with a specific function after 19th Century neurologist Paul Broca autopsied a man who had lost the ability to speak.
When examining the man’s brain (you can see it on the right), Broca found selective damage to the third convolution of the left frontal lobe and linked this with the fact that the person could understand speech but not produce it.
This type of speech problem after brain injury is now known as Broca’s aphasia but his innovation was not simply naming a new type of neurological problem.
Broca was one of the first people to think of the brain in terms of separate areas supporting specialised functions and studying patterns of difficulty after brain damage as a way of working this out – a science now known as cognitive neuropsychology.
The patient Broca described was nicknamed ‘Tan’ because this was the only syllable he could produce. The scientific report named his as Monsieur Leborgne but no further details existed.
Oddly, personal details were not even recorded in Broca’s unpublished medical notes for the patient.
Because of the mystery, people have speculated for years about the identity of Monsieur Leborgne with theories ranging from the idea that he was a French peasant to a philandering man struck down by syphilis.
But now, historian Cezary Domanski has tracked down the identity of Broca’s famous patient through detective work in record offices in France and published the results in the Journal of the History of the Neurosciences.
According to the Broca’s report, the health problems of Louis Victor Leborgne became apparent during his youth, when he suffered the first fits of epilepsy. Although epileptic, Louis Victor Leborgne was a working person. He lived in Paris, in the third district. His profession is given as “formier” (a common description in the nineteenth century used for craftsmen who produced forms for shoemakers).
Leborgne worked until the age of 30 when the loss of speech occurred. It is not known if the damage to the left side of Leborgne’s brain had anything to do with traumas sustained during fits of epilepsy nor, as reported in some recent publications, does it appear to have been caused by syphilis, as that was not indicated in Broca’s reports. The immediate cause for his hospitalization was his problem with communicating.
Leborgne was admitted to the Bicêtre hospital two or three months after losing his ability to speak. Perhaps at first this might have been perceived as a temporary loss, but the defect proved incurable. Because Leborgne was unmarried, he could not be released to be cared for by close relatives; he therefore spent the rest of his life (21 years total) in the hospital.
Domanski’s article finishes on a poignant note, highlighting that Leborgne became famous through his disease and death and his life history was seemingly thought irrelevant even when he was alive.
“It is time” says Domanski, “for Louis Victor Leborgne to regain his identity”.
Link to locked article on the identity of Broca’s patient (via @Neuro_Skeptic)
11 thoughts on “Owner of Broca’s area identified”
1. Technically, Leborgne could say more than just the word “tan”. Apparently he could curse quite well (a feature not uncommon in expressive aphasia, interestingly). But I guess referring to him as patient “Merde” in the literature was seen as uncouth.
1. I thought so also but apparently this is a common confusion with another of Broca’s cases.
From Domanski’s article:
1. From Broca’s Remarks on the Seat of the Faculty of Articulated Language,
Following an Observation of Aphemia (Loss of Speech)
2. I got this reply from Cezary Domanski. This is posted here with his permission:
Thank you for taking interest in my paper.
2. {chuckles} True.
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<urn:uuid:ba4aa4a1-cb52-4b24-a404-447f104801b1>
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Have you been wondering how U values for windows are calculated, and why different suppliers and different countries seem to use different numbers?
Let's start by looking at the basics, as getting a handle on the fundamentals is critical.
What is a U value?
According to, a “U-value measures how well a product prevents heat from escaping. It is a measure of the rate of non solar heat loss or gain through a material or assembly. The lower the U-value, the greater a window's resistance to heat flow and the better its insulating value.”
Also, a U value is the opposite of an R value. The R value measures thermal resistance of an element as opposed to its conductivity. Hence, an element’s R value is simply 1/U, and conversely, U = 1/R. It therefore follows that higher R values are better thermal performers.
That’s a bit confusing in Australia, because we use U values for windows, and R values for walls and roofs and floors (if you are including insulation in the floor, which in the colder parts of our country, you really should be doing).
In Europe, however, they use U values to describe walls as well as windows.
Furthermore, a U value is different from an SHGC value. The SHGC (solar heat gain coefficient), or g value measures solar heat gain and is expressed as a percentage. The higher the percentage, the higher the heat gain through the element.
In hot parts of the world, you don’t want a high SHGC – you want a lower one. But you also want an effective (lower) U value to stop the heat transferring into the building (and to stop the cool temperatures moving out of the building).
A U value must be calculated or assessed for both the window frame as well as the glazing itself. Because a frame is made of different material from glass, two U values must be determined. The frame's U value is often referred to as the Uf value.
The glazing-related value, called the Ug value, relates to the glazing unit part of the window, which includes the glass itself as well as the gaps between the panes (if double or triple glazed).
Therefore the goal is to combine the two separate U values (the Uf and the Ug) to determine the U value for the entire window as a whole (or the Uw value).
Frames typically provide higher U values - or worse performance - than glazing, particularly if you are looking at double or triple glazing. That means that if you have a small window to calculate, with a Ug of 0.6, the small window will come out with a worse Uw rating (higher U value) than a large window simply because the small window has more frame in proportion to the glass.
This is an important point to note because it makes one aware that there is no such thing as a standard U value for a whole window setup (Uw) regardless of its actual size. You will always need to calculated a Uw value for the exact size and shape of the window unit as the proportions between frame (Uf) and glass (Ug) will always change depending on the window’s size and configuration.
If you are ordering 10 windows of different sizes, you may end up with 10 different Uw values for your project, even though the exact same glazing and exact same window frame profiles are used throughout.
The next confusing issue is that of measurement units themselves: imperial vs metric. Australia and Europe follow the metric system, so the U value is described as watts per metre squared multiplied by degrees Kelvin (W/m²K).
In reality, most European windows come with lower U values (higher performance) than Australian windows because European windows are constructed differently, with different materials.
Imperial measurements are utilised in the US, which causes a lot of confusion with the rest of the world. Indeed, one green building journalist in the US wrote about our Superpod certified passive house, saying that he could not understand how our building was high performing, because he thought that the insulation was so thin. The issue was that European U values are not the same as US values and he had failed to make the proper conversions.
A detailed review of the US vs EU standards is found in the paper International Window Standards, Final Report/April 2014 for the Homeowner Protection Office, branch of BC Housing, by RDH Building Engineering Ltd in Canada. The paper says that “there is no straightforward way to compare North American and European product performance.” It reviews in great detail the differences between window rating systems in North America, Europe, and for passive house.
The mathematics behind U values can get quite complicated. Suffice it to say that there is a rule of thumb for converting metric and imperial U values, and that is to divide the metric U value by 5.6783, in order to get the imperial equivalent. This means that a U value of 1 in the EU will be (roughly) equivalent to a U value of 0.174 in the US - assuming the same testing methodology for that window.
Let’s now consider that last point regarding testing methodologies. There is a voluntary window organisation in Australia called WERS: the Window Energy Rating Scheme. It is run by the Australian Window Association (AWA). If you are a member of the AWA, you can participate in WERS, and you can see WERS ratings for different window companies specified on their website.
The WERS website says members must obtain energy ratings for their products from a rating organisation that is accredited by the Australian Fenestration Rating Council (AFRC), which is an incorporated entity and not a government body. The AFRC states on its website that it “will develop, administer and approve the only uniform, independent, comparative rating and labelling system for the energy performance of windows.”
In a similar way, European made windows must be tested against European standards. For a certified passive house, your windows must be accompanied with a certificate to the EN Standard. EN Standards are documents that have been ratified by a European Standardisation Organisation for the purposes of EU Regulation. There are also DIN standards in play throughout Germany. There are literally thousands of EN standards for things as varied as cork floor testing and electromagnetic compatability emissions standards for industrial environments. The US has its own standards and compliance testing facilities.
As noted above, most Australian windows have higher U values than European windows because of the different materials used. This in turn is partly due to more stringent legal requirements. Germany, for example, has mandated low U values for some time (generally under Uw 2).
In contrast, according to WERS, "U-value ratings generally fall between 2.0-10.0 W/m2.K for Australian products."
But there’s another thing: if a window company says that all their windows have Uw values equal to 3, they are not providing accurate or practically useful information. There would be different Uw values depending on the actual size and configuration of each and every window.
Furthermore, if you want your house to be certified as a passive house, the detailed and structured building physics modelling program (the Passive House Planning Package) requires proper EN standard compliance regarding U value reporting, and checks the sizes of each window carefully. Consequently, the passive house program requires the specific Ug and Uf values to be separately nominated. If you really want to model the heat loss of any window, you need to calculate the heat loss through that size of glass as well as the size and shape of the frame, to consider the whole effect of that particular window.
Also, U values say nothing about the installation methods (which the Passive House Standard also requires to be nominated and verified), air leakage, quality of production, or tolerances. How many of us have watched those "Grand Designs" episodes where the windows are 10 millimetres out? Your window should fit. In Australia, our building code tolerances may allow for things that are just not going to cut it if you want the building (and the windows) to actually perform.
So there is much to watch out for. If we understand what is being reported when numbers, ratios or percentages are being bandied around, we will know better what is being assumed, and what is being accurately calculated.
Co-written by Fiona McKenzie and Harry Strouzas
• Hi Fiona,
good article, full of information. But the different U-values between Europe and Australia are not only due to the frame material itself but also with the MANDATORY window sizes which are tested. In Australia window sizes for U-value testing are 600mm wide x 1500mm high = 0.9m2 (WERS testing), in Europe the size tested is up to 2.3m2 (1.23×1.48m). This means that in Europe the frame itself is a much smaller percentage in comparison to the glass than in Australia, a reason why U-values vary between continents for the exact same make of window – as you also pointed out. The European style tilt & turn window made locally here in Australia (e.g. by Paarhammer) is exactly the same as in Europe using the very same hardware fittings imported from Germany, but get different U-value ratings as Australia follows the US system for the testing. For manufacturers to test every window size is totally impractical (and also very costly which would make good windows here even more expensive) but you are correct in saying that the window industry in Australia still has a long way to go for most of its products to be truly energy efficient. A start would be to make WERS testing mandatory to ensure customers have a way to compare all locally made products.
• Thanks Edith! Appreciate your comments.
We are making the comment in the article that "there is no such thing as a standard U value for a whole window setup (Uw) regardless of its actual size."
If people use a Uw value which is said to be the same across different window sizes, they are referring to a nominal or hypothetical Uw value. Real Uw values will differ according to the size and shape of each window frame.
That means that, as you say, if you are comparing nominal values from different hypothetical base lines, you are not comparing apples with apples. So you may get different nominal U-values using different hypothetical-based systems, not because the physics is any different, but because you are really comparing different nominal window sizes.
When we design our certified passive houses with Superpod, or when anyone designs a house to the Passive House Standard using the International Institute's modelling program, the U value of each window must be calculated separately so that the size and shape of the window is correctly taken into account.
That is one of the benefits of using raw data (Ug and Uf) in a design process. The Passive House Institute does not test every window size, it takes the U value of the frame, the U value of the glass, the length of the frame etc, and just does the maths through the physics program.
• Great work, Fiona, it's a tricky and complex area!
Re "the U value is described as watts per metre squared multiplied by degrees Kelvin (W/m²K)." – I suggest thinking of the U-value metric as watts transferred through each square metre of window (or other element) for each degree in temperature difference between the inside and outside. So it's much more heat loss if the temperature difference is greater.
• Hi Fiona,
Good to see articles recognising high performing window systems and the importance of ensuring the testing of these is up to scratch.
I wanted to quickly point out a few areas that seem to have been skirted over in the article. 1.You showed how Imperial and Metric units are different, however you didn’t mention the underlying differences between the European testing and the Australian testing such as, European testing ignores the edge of glass performance which differs from both the frame and glass U and that the European method uses different temperature conditions for measurement. 2. You also discussed that U values for windows will vary for each different size, which is correct, however under the AFRC requirements (that are called up by the NCC) windows are to be calculated according to prescribed standard sizes. The AFRC and WERS operate a comparative rating system which allows the comparison of window systems on a like for like basis.
I also want quickly mention that poor installation is the cause of close to 90% of issues in our industry. WERS would love to work with the Passive House industry to ensure a level playing field and a better industry. Richard
• Great points Richard!
• Thanks Richard. Appreciate the feedback.
We totally agree with you that installation is a massive issue. In recent discussions with an architect, they bemoaned the fact that they could specify high performance windows, but had no say over how they were installed. In a passive house project they designed, not only were different windows substituted, but the installation was poor.
Procurers of high quality passive house buildings will need to learn that they can't just go with the cheapest quote for installation. Proper installation takes care and TIME! That means it will cost more.
Regarding your point 1., are you saying that the European and Australian methods of assessment of a U value (as opposed to testing physical sizes of windows) are not comparable? Would be interested to see your basis for that, and any references would be useful.
We understand the comparative rating system that the AFRC and WERS are aiming for, however, we find it to be confusing to some, because people think that all the windows they buy from company x are U value y. That's why the Passive House Standard, which is aiming for best practice building performance, will not accept an overall Uw value regardless of the size of window.
It's important that people understand what assumptions are behind claims being made for more sustainable buildings. It's part of our mission to improve clarity there. See, for example, our sourceable article on airtightness assumptions for Energy ratings – something that is never tested!
If people understand what assumptions are being made, and they buy products fully informed, well and good! Hopefully our article goes some way towards assisting there.
Perhaps WERS could look at courses for installation?
• Great article Fiona. I found your information to be very thorough. I have recently read the Dowell window website. It seems that they provide a wide range of windows in different sizes and thicknesses for different geographic locations and also for different walls in each house, for example they recommend different types of windows for each side of the compass. I can well imagine that most builders will neglect to take advantage of the choices available. Only one project home salesman out of many, promoted the fact that his company provide a better quality window than their competition. Does that mean that it is not important or that profit is the only priority?
• Thanks Joan. Interesting questions you pose! Certainly window quality is important for the consumer, the occupier, the investor, the operator of a building. It might not be important to a builder or developer who simply wants to make the best and easiest profit. That would be partly because the builder or developer is not going to occupy the building! It might help if customers start asking builders and developers the right questions, as you are doing. Also, we challenge builders and developers to start taking more responsibility for their decisions and actions and to be a little more creative in providing consumers with high quality buildings that don't waste energy. This might involve them changing their marketing strategies and even educating consumers. Perhaps they could spend less on expensive decorative elements, focus more on the joy of living inside a well designed building, and market that more effectively to the consumer. Some are starting to dabble in this. Perhaps they can increase their profit margin, or at least keep it the same, who knows?
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George washington
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George washington
1. 1. George Washington<br />By: Mr. Rob Diedrich<br />EDU 290<br /><br />
2. 2. Who was President George Washington?<br />George Washington was born on February 22, 1732.<br />Born in 1732 into a Virginia planter family, he learned the morals, manners, and body of knowledge which was standard for an 18th century Virginia gentleman. <br />He pursued two intertwined interests: military arts and western expansion.<br /><br />
3. 3. Washington’s Childhood<br />George was the first child of Augustine Washington and his wife Mary Ball Washington. <br />He was born on their Pope’s Creek estate in Westmoreland, Virginia. <br />His Father was very wealthy. George would have been raised with the greatest education.<br />
4. 4. Washington as a Young Soldier<br />By 1754, Washington had become lieutenant colonel and fought in the first skirmishes of the French and Indian War.<br />In a legendary story Washington escaped four bullets which went through his coat, but he was unharmed. <br /><br />
5. 5. Washington as an American Rebel<br />In the time between the French and Indian War and the American Revolution Washington spent his time as a farmer near Mount Vernon.<br />He like other planters of this time had many issues British merchants and regulations.<br />Washington was known for his resistance against the Mother country’s oppression. <br /><br />
6. 6. Washington as a Commander<br />When the Second Continental Congress assembled in Philadelphia in May 1775, Washington, one of the Virginia delegates, was elected Commander in Chief of the Continental Army.<br />On July 3, 1775, at Cambridge, Massachusetts, he took command of his ill-trained troops and embarked upon a war that was to last six grueling years.<br /><br />
7. 7. Washington and the Constitution<br />Washington was crucial in the steps leading to the Constitutional Convention at Philadelphia in 1787.<br />When the new Constitution was ratified, the Electoral College unanimously elected Washington President.<br /><br />
8. 8. How he felt about the Constitution<br />Washington was one of the first to recognize that the articles were flawed, so he pushed for the constitution.<br />He believed strongly that states rights and the protection of such rights were of upmost importance to the new government.<br /><br />
9. 9. Washington During the French Revolution <br />When the French Revolution broke out under Washington’s Presidency he was faced with a serious turning point.<br />Thomas Jefferson the Secretary of State was very French biased and Alexander Hamilton the Secretary of Treasury favored the British.<br />Very famously Washington took the middle ground and refused to back either side in their war. <br />
10. 10. America’s 1st President<br />George Washington was elected unanimously in 1789 and again in the 1792. <br />To this day he is the only President to receive 100% of the electoral college votes. <br />John Adams took the role of Vice President.<br />
11. 11. Washington’s Fears<br />President Washington was very against the two party system because he believed that it would create a government with extreme right and left views.<br />In Washington’s farewell speech he addressed these concerns and urged that long term alliances would be a huge mistake.<br />
12. 12. Famous Quotes<br />Associate with men of good quality if you esteem your own reputation; for it is better to be alone than in bad company.<br />Be courteous to all, but intimate with few, and let those few be well tried before you give them your confidence.<br />Few men have virtue to withstand the highest bidder. <br />
13. 13. Famous Quotes<br />Firearms are second only to the Constitution in importance; they are the peoples' liberty's teeth.<br />I can only say that there is not a man living who wishes more sincerely than I do to see a plan adopted for the abolition of slavery. <br />
14. 14. Washington’s Death<br />He died of a throat infection December 14, 1799. For months the Nation mourned him.<br /><br />
15. 15. Work Citied<br /><br /><br /><br />
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Water Quantity
Students simulate the amount of fresh water available on earth by removing measured amounts of water from a five-gallon bucket. Students explain why some of the earth's fresh water is not readily accessible and is relatively scarce.
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Dave L.
Dave L., Teacher
San Antonio, TX
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IUCN threat status:
Least Concern (LC)
Life History, Abundance, Activity, and Special Behaviors
These frogs can be long-lived and have a potential life-span of at least 15 years (Leenders 2001). Adults are nocturnal and stay in hiding during the day, sheltering in subterranean burrows, beneath logs, in the spaces between tree roots, or under houses (Savage 2002). Juveniles, however, are active during the day and can be found on top of the leaf litter (Savage 2002). This species prefers dimly lit forest (Jaeger and Hailman 1981). At the first sign of dusk, males of this species give off a loud "wrooop" (Leenders 2001). The call lacks pulses (Hero and Galatti 1990). Males are territorial and call sporadically from burrows located underneath a log or rock, often in densely vegetated areas (Leenders 2001).
Mating is believed to take place throughout the rainy season months of May to November (Savage 2002). However, Hero and Galatti (1990) observed that males in the central Amazon region of Brazil began calling immediately after the first substantial rains, in late September, and that calling ceased after two to four weeks. Both calling and breeding take place at the water's edge; it is not known whether the same burrows used for shelter are also used as nest sites (Savage 2002). Amplexus is axillary in this species (Savage 2002). As the male hugs the female under the armpits with his robust forearms, he creates a large foamy mass around the eggs by rapidly moving his back legs through the jelly surrounding the fertilized eggs (Heyer and Rand 1977). This foam nest consists of a frothy mix of sperm, skin secretions, water, and air (Heyer and Rand 1977). Females lay about 1,000 light gray eggs, and the foam nests are constructed in dry cavities or depressions (Savage 2002). These hollows may be natural or possibly excavated by the males (Muedeking and Heyer 1976). Foam nests may be constructed near puddles, temporary pools or in seasonally flooded spots, such that rain washes the larvae out of the nests and into nearby small rain pools (Breder 1946). Alternatively, foam nests have been observed in open depressions at some distance from water, so that tadpoles develop within the nest until metamorphosis (Muedeking and Heyer 1976; Hero and Galatti 1990). In the latter case, Muedeking and Heyer (1976) noted both larvae and eggs in the nests, and inferred that eggs were being consumed by larvae. Leptodactylus pentadactylus larvae are unusually resistant to desiccation for anuran tadpoles, and can survive almost seven days out of water (Valerio 1971). Foam nests also provide protection to larvae from desiccation (Heyer 1969).
Galatti (1992) observed that the strong seasonality in Leptodactylus pentadactylus reproduction in Brazil coincided with arthropod prey availability. He observed two peaks in arthropod abundance, one in late September (when the adults arrived at breeding sites), and the second in January and February, when tadpoles completed metamorphosis into juvenile frogs (Galatti 1992). These peaks did not completely correspond to rainfall, as the first peak in arthropod prey abundance occurred during the late dry season and the second occurred during the wet season (Galatti 1992).
Leptodactylus pentadactylus is able to secrete huge amounts of mucus as an antipredator defense (Savage 2002). In addition to making the frog slippery and difficult to hold, the skin secretions are toxic (Savage 2002). Savage (2002) points out that this toxicity is evident both from direct contact (resulting in human skin rashes and stinging) and indirect contact, from being in the same room when the frog is handled (which results in sneezing and swelling of human eyes and mucus membranes). The residue from these skin secretions is lethal to other frogs which come in contact with it (Savage 2002). Leptodactylus pentadactylus also exhibits defensive behavior, which consists of facing the predator, inflating and elevating the body with all four limbs (Villa 1969; Savage 2002). This has the effect of raising the posterior, glandular surfaces above the level of the head since the hind limbs are longer (Villa 1969; Savage 2002). Initial elevation is followed by repeated raising and lowering of the body (Villa 1969; Savage 2002).
These frogs are opportunistic feeders. Adults consume anything that they can swallow, including bird chicks, snakes, other frogs (particularly dendrobatids, despite their toxicity), and scorpions (Leenders 2001). Tadpoles initially feed on the foam produced by the male, but later will either eat algae (Vinton 1951) or become carnivorous, preying on eggs and tadpoles of their own species or other species (Muedeking and Heyer 1976; Heyer et al. 1975).
Predators on Leptodactylus pentadactylus eggs include the ephydrid fly Gastrops willistoni, which lays its own eggs on L. pentadactylus clutches in Costa Rica and Brazil (Villa et al. 1982). Predators on the adult frogs include coatimundis, snakes, and caimans. When discovered, these frogs often remains still and easily approached. If caught, however, they will emit an extremely loud, high-pitched scream to startle potential predators (Leenders 2001).
Research has shown that these frogs have an accurate visual image of their surroundings, though it is not known exactly what cues they use for orientation (Leenders 2001). Frogs taken from their burrows and displaced over short distances have managed to return to their burrow in a straight line (Leenders 2001).
Adult Leptodactylus pentadactylus are negatively phototactic (avoid light), unlike most anurans (Kicliter and Goytia 1995).
Creative Commons Attribution 3.0 (CC BY 3.0)
Source: AmphibiaWeb
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NCPA - National Center for Policy Analysis
Lessons In Leadership
June 11, 2001
In the 19th century, private expeditions to the Arctic region achieved more success with fewer resources and fewer casualties than government-sponsored exploration. Why was the private sector more efficient and successful?
According to economist Jonathan M. Karpoff, who examined 92 expeditions from 1818 to 1909, the private expeditions were better organized and led.
• In 77 percent of private expeditions, the leader initiated, planned and led their teams, increasing their motivation and preparation; but only 26 percent of leaders of public expeditions did so.
• Moreover, private leaders delegated decisions more often, solicited and used crew information and participated in menial chores.
• By contrast, the hierarchical leadership structure of public expeditions prevented a flow of information between the leaders and the crew, reducing efficiency.
The teams assembled by the private expeditions' leaders were better:
• Private expeditions proved to be more adaptable and better able to learn from their mistakes than public expeditions.
• Private crews were usually seasoned travelers, whereas public crews were less accustomed to the terrain.
• Also, private crews voluntarily chose to be part of the expeditions, while public crews were often appointed -- and thus less motivated.
Finally, another important factor was the incentive for success. Public employees were paid regardless of their achievement, while private employees received additional payments for reaching their goals.
These differences between private and public efforts can be seen today in modern industries and government agencies. This suggests the entrepreneurial private sector has advantages in motivation, organization and incentives over government efforts, regardless of the century.
Source: "Lessons from the Arctic," Economic Intuition, Winter 2001; based on Jonathan M. Karpoff, "Public versus Private Initiative in Arctic Exploration: The Effects of Incentives and Organizational Structure," Journal of Political Economy, February 2001.
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Guillotine History
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"Mademoiselle Guillotine"
During the course of the French Revolution, the persistent rebels finally achieved their goal and overthrew the tyrannical monarchy. However, even after this initial struggle came even greater bloodshed, for the rebels proved they could be just as brutal as their old oppressors. Yet, this brutality would never have been as extreme as it was were it not for the invention of the infamous guillotine. A dark machine designed for decapitation, it consists of a tall, wooden frame in which a heavy, sharp blade is suspended. Through the use of rope, this blade could be raised to its peak and then, upon releasing the rope, would be allowed to fall freely so that it swiftly crashes down upon its victims' soft necks. While similar methods of execution had existed for many centuries, the guillotine easily stands out among the rest due to the incredible number of heads it has so efficiently sliced off.
In Ireland, during the year 1307, there is a record of a machine known as the Scottish maiden, which was used to take a man's life through the method of decapitation. This device is perhaps one of the most primitive forms of the guillotine seen in the revolution. The maiden, along with the Halifax gibbet, a similar invention, gradually gained popularity, being used in places such as Italy and Switzerland during the 15th century. However, it was not until the 1700's that these machines were altered and improved to become the modern guillotine. Named for Joseph-Ignace Guillotin, a French doctor and member of the Revolutionary National Assembly, he believed that the guillotine provided a previously unseen humane manner of execution. Prior to its usage, criminals typically hoped to be executed by an axe man or swordsman, which, in contrast to torturous deaths like being set on fire or broken on the wheel, gave relatively quick deaths. Yet, there was always the unlucky convict who received a deep chop in the shoulder because his executioner had bad aim...
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A new discovery shows how wing spots evolved in a species of polka-dotted fruit fly, and underscores the concept that evolution likes to tinker with existing genetic machinery.
One lesson here is that complexity can be generated in pretty simple ways.
Sean B. Carroll
“When nature invents, it does so by using what is readily available,” says Carroll, also a professor of molecular biology and genetics at the University of Wisconsin, Madison. The new report is published in the April 7, 2010, issue of Nature.
Carroll has spent his career studying how evolution occurs at the genetic level, pinpointing many of the molecular changes that lead to new traits and new species. Most of Carroll's discoveries have come to light by studying the common fruit fly Drosophila melanogaster, the workhorse of modern molecular genetics. For the current study, though, Carroll and colleagues focused on Drosophila melanogaster's prettier cousin, a polka-dotted fly species called Drosophila guttifera. Unlike the rather plain D. melanogaster, which has spotless wings, each D. guttifera fly boasts 16 black spots and four gray swatches on each wing. Carroll says the pattern likely evolved to help the flies attract mates or to provide camouflage from predators.
In earlier research, Carroll's group traced the spots on D. guttifera to a pigment-producing gene called yellow. He also found that the wing spots appeared only after a particular genetic switch, called a regulatory element or an enhancer, switched on the yellow protein in specific cells. Regulatory elements bracket the coding regions of genes, and switch a gene on or off in particular tissues or at certain times during development. Much of Carroll’s research has explored the evolutionary role of these switches, finding that small changes in them can account for large differences in morphology and appearance.
For the new study, Carroll and his team discovered that all 16 spots on each wing are produced by a single enhancer region near the yellow gene. This discovery was a “great hint,” says Carroll, that a single molecule might act as an input that triggered the formation of all the spots. “If you had spots in one place governed by one piece of regulatory DNA and spots in another place governed by another piece of DNA, we would have been suspicious that there were different inputs and the pattern was sort of put together pell-mell,” says Carroll. “But the fact that there was one regulatory element made us think that there was one triggering molecule at play.”
Carroll and his team garnered another critical clue by observing their large colony of D. guttifera. As lab workers sorted the flies, they set aside individual flies that had irregular spots. Curiously, each mutant fly with an extra spot also had an extra sensory organ—a motion detector called a campaniform sensillum—under the spot.
Conversely, flies missing a spot were also missing the underlying sensory organ. Carroll concluded that the base topography of the wing—namely its prominent veins and sense organs—provided an underlying pattern that the spots covered over later in the species’ evolution. “Evolution is really painting the spots on top of a landscape that has already been determined,” says Carroll. This observation fueled Carroll’s speculation that a single input molecule —one also involved in the development of the wing structures, perhaps—might be at play in triggering the spots.
Carroll and his colleagues then took the yellow enhancer regions from D. guttifera and spliced them into D. melanogaster to see what impact these snippets of DNA might have on a closely related species whose genetics were well known. The D. melanogaster flies did not develop spots, but the enhancer region produced a distinctive pattern in wings of the developing flies, showing up in the veins and along the edges of the wings. Whatever factor drove the production of yellow in D. guttifera also appeared to be active in the region of D. melanogaster's wing that bore the distinct pattern.
Carroll showed the pattern to two D. melanogaster experts, Seth Blair at the University of Wisconsin, Madison, and Ethan Bier at the University of California, San Diego. They both said, “That looks wingless-y.” That is, the pattern closely matched the distribution in D. melanogaster of expression of a key developmental gene called wingless. Carroll calls wingless “part of the toolkit of animal development,” because it is repeatedly used to help shape the basic body plan of an animal. It is wingless’s job to place appendages in the right spot and ensure that wings develop in the proper location. It is one of the most studied genes of all time, Carroll says, noting that entire laboratories of fruit fly geneticists are devoted to exploring its activities.
To see if wingless triggered the spots in D. guttifera, Carroll and his team isolated the wingless gene in that species and hitched the gene to a fluorescent protein to illuminate where in the fly's body the gene was active. The experiments showed that late in wing development, wingless appeared in the 16 spots. “Whereas Drosophila melanogaster deploys wingless in a certain pattern, D. guttifera deploys wingless in these new areas which correspond perfectly to the polka dots,” says Carroll. “As soon as we saw that, that was bingo, rock ‘n’ roll, eureka, whatever cliché you want to use. That was it.”
At some point in D. guttifera’s evolutionary past, Carroll concluded, wingless took on the new job of turning on the yellow pigmentation gene. Once that linkage was established, producing new spots became as simple as producing wingless in a particular pattern. “One lesson here is that complexity can be generated in pretty simple ways,” says Carroll. “Another is that evolution does a good job of making new patterns out of materials that already exist.”
Carroll says the basic principle of using a single input molecule to determine a complex skin pattern may apply to other insects, too. “I’m not going to say this is the key to the whole kingdom of animal patterns and colors,” he says. “But it’s a pretty good example of a strategy that might be used in the generation of color pattern diversity in ladybug beetles, dragonflies, butterflies, and so on. This is probably a glimpse into the general logic of how it happens.”
He adds that his group's new Nature paper unravels an elegant evolutionary mechanism. “This is what draws a lot of people to biology – the beautiful patterns and the mystery of the origins of them,” he says. “And it’s not that often that we get to peel back the onion and really figure out what’s at the core.”
For More Information
Jim Keeley 301.215.8858
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Definition of tenor noun from the Oxford Advanced Learner's Dictionary
BrE BrE//ˈtenə(r)//
; NAmE NAmE//ˈtenər//
People in the music world
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1. 1 [countable] a man’s singing voice with a range just below the lowest woman’s voice; a man with a tenor voice compare alto, baritone, bass1, countertenor See related entries: People in the music world
2. 2[singular] a musical part written for a tenor voice
3. 3[singular] the tenor of something (formal) the general character or meaning of something I was encouraged by the general tenor of his remarks.
4. Word Originnoun senses 1 to 2 late Middle English: via Old French from medieval Latin, based on tenere ‘to hold’; so named because the tenor part was allotted (and therefore “held”) the melody. noun sense 3 Middle English: from Old French tenour, from Latin tenor ‘course, substance, import of a law’, from tenere ‘to hold’.Extra examples The whole tenor of the meeting was very positive. Three celebrated tenors sang at the president’s inauguration. We persuaded Jake to sing tenor. The general tenor of her argument was that Parliament should redress the balance between rich and poor.
See the Oxford Advanced American Dictionary entry: tenor
Other results
All matches
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Amy Mann
Mesopotamia's Art/Architecture
Mesopotamian's had a lot of interesting art. They made jewelry out of imported gold, silver, and gems. They also made cylinder seals. These were stone cylinders engraved with designs. When rolled over clay, each seal would leave an imprint. Each seal had it's own individual imprint.
Mesopotamian's built ziggurats, which were pyramid-shaped temples or towers. The main building block that they used for houses were bricks made out of mud.
Cylinder Seals
Mesopotamia's Achievements
The more Mesopotamian society advanced, the more achievements they made. One of these achievements was the invention of the wheel. They eventually used the wheel to build chariots and pottery wheels.
Another achievement they made was irrigation systems. Irrigation systems were a series of canals dug into the ground to control water for farming.
Mesopotamian's also had the first written laws, called Hammurabi's code. This was a set of 282 laws written in stone that dealt with almost every part of daily life.
Hammurabi's Code
Mesopotamia's System of Writing
Mesopotamian's used cuneiform as their system of writing. Since they didn't have pen, pencils, or paper, they used sharp tools called styluses to make wedge-shaped symbols on clay tablets. They also used pictographs, which were picture symbols. As time went on, the pictographs became better.
Cuneiform Alphabet
Mesopotamia Video
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Saturday, February 13, 2016
What are Horns and Antlers?
What are Horns and Antlers?
A common mistake made when speaking of protrusions coming out of the heads of animals is mistaking antlers and horns. While the two can be very similar in some aspects, they are also very different. When it comes right down to the bony details, it can actually be very easy to tell them apart. And why horns and antlers are even there in the first place is fascinating. First of all, let's talk about how to tell these two body parts a part.
Similarities of Horns and Antlers
First: what are horns and antlers? As stated before, they are protrusions coming from the top of an animal's head. Both horns and antlers help protect the animal. They're often used for fighting -- to fight for anything from dominance, to territory -- and also to attract potential mates. Have you ever seen a ram, for instance, head butt another ram with its horns? This is a learned behavior, and is carried over from when sheep and rams ran in the wild. (1) Rams use their big, strong horns to fight for dominance -- to see who is most fit to lead to lead their herd. (2)
Another similar trait about both Antlers and Horns is that they're both made bone. This makes them strong, and able to withstand all the fighting they do.
Differences of Horns and Antlers
Horns and antlers may have some things in common, but they are much, much different. Their differences start from how they grow on the animal. Horns start to grow soon after the animal is born, and they continue to grow with the animal throughout its lifetime! Horns have a bony structure underneath, and on top, they are covered by something called a sheath. This sheath is made up of something called keratin. Keratin is what your fingernails and even your hair is made out of! (3) Horns do not shed at all. They're stuck their on the animal's head permanently -- forever. Their whole lives. Horns also, usually, don't have any branching or forking. For instance, a tree has branches all over, coming from its trunk. Antlers are the same way. But most horns don't have anything resembling any kind of branch. As with every rule, though, there is always an exception. The Pronghorn Sheep (4) has horns, but they also do fork out the tiniest bit! You can see examples in the pictures below! (5,6)
(Horns on a Ram)
(Horns on a Pronghorn Sheep)
Antlers, on the other hand, or ...should I say, the other head? Antlers don't have a protective covering at all. It's just the bone. Throughout the animal's lifetime, the antlers actually fall off, or shed, and come back! Could you imagine part of your body falling off? What if your ear were to fall off and then grow back later? When the antlers shed off, they actually grow back bigger and even stronger than they were before. These antlers also fork or they branch off, like mentioned before. You can see the difference between antlers that fork, and antlers that branch down below! (7,8)
(Antlers on a mule deer that fork)
(Antlers on a whitetail deer that branch)
Fun Facts about Horns and Antlers!
• Did you know that Rhinos are the only mammal that has a horn on its nose! (9)
• Did you know that Giraffes have horns, but their horns don't have a keratin sheath like other animals with horns! Instead, their horns are covered by a thin layer of hair. (9)
• Did you know that Caribou are the only animal species where both the male and female have antlers? (9)
• 1) (2015, Sep 21) Sheep 101: head butting by rams
2) Alina Bradford, (2014, July 31) Rams: Facts About Male Bighorn Sheep: LiveScience
3) Emily Graslie (2013, Mar 18) Horns vs. Antlers - The Brain Scoop
4) Kara Kovalchik (2014, Mar 6) What's the Difference Between Antlers and Horns? - Mental Floss Website
5) Picture of Ram provided by
6) Picture of Pronghorn Sheep provided by
7) Picture of Mule Deer provided by
8) Picture of Whitetail Deer provided by
9) (2015)
Feb 13, 2016 - Written by Mariah Loeber
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The Pourquoi Tale Of How The Bear Lost His Tail: Question Preview (ID: 20217)
Below is a preview of the questions contained within the game titled THE POURQUOI TALE OF HOW THE BEAR LOST HIS TAIL: This Activity Will Be Used To Determine How Well First Grade Students Comprehend The Main Elements Of The Iroquois Indian Tale And What A Pourquoi Story Is. To play games using this data set, follow the directions below. Good luck and have fun. Enjoy! [print these questions]
What are pourquoi stories?
a) tales that explain why something is the way it is b) stories about sports c) stories about cooking d) tales about a dragon
What does Pourquoi mean?
a) It is French for how. b) It is French for why. c) It is French for animal. d) it is French for food.
What do pourquoi tales describe?
a) They describe how to play baseball. b) They describe how to cook food. c) They describe something in nature, like animals. d) They describe how to avoid strangers.
Who were the main characters in the tale How Bear Lost His Tail?
a) Cat and Bear b) Snake and Bear c) Bear and Fox d) Fox and Horse
What was the setting of the story?
a) in a cave at the base of a mountain b) on a frozen lake during winter time c) in the forrest during fall d) in a meadow during spring time
What was Bear's proudest possession?
a) his sharp claws b) his brown fur c) his honey d) his long tail
What did Fox have that Bear wanted?
a) a handful of berries b) yummy honey c) big trout and fat perch d) nothing
What character quality best describes Bear?
a) honest b) selfish c) giving d) trusting
What character quality best describes Fox?
a) selfish b) giving c) sly d) honest
What did Fox tell Bear to use to fish with?
a) his hand b) his tail c) a stick d) his snout
Play Games with the Questions above at
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Websites and Directions for PowerPoint
Directions for Explorers PowerPoint:
1. You and a partner will research four European explorers:
- John Cabot
- Henry Hudson
- Ponce de Leon,
- Robert de la Salle
2. Your PowerPoint presentation should include the following:
- a Title slide (include a picture of the four explorers as well as you and your partner’s names)
- One slide for each explorer showing a map of the explorer’s voyage(s) as well as a description of where the person explored and when this trip was made
- One slide for each explorer that explains the purpose of the voyage (why was this person making this trip, what did this person hope to find)
- One slide for each explorer that explains the accomplishments of the explorer (what did this person discover, what were the effects of the discovery)
- Bibliography (what websites were used to help you create this PowerPoint)
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Teaching Quilombismo: An Afro-Brazilian Political Philosophy
Image Credit: Carlos Moura/CB/D.A Press. Brazil.
Abdias do Nascimento. Image Credit: Carlos Moura/CB/D.A Press. Brazil.
In 1980, Abdias do Nascimento, one of Brazil’s greatest black activists and intellectuals, published a seminal essay titled “Quilombismo: An Afro-Brazilian Political Alternative.” Based on his address to the Second Congress of African Culture in the Americas, the essay was a sweeping declaration of black rights, asserting “the urgent necessity of Black people to defend their survival and assure their very existence as human beings.”
He strategically called this ideology “quilombismo,” a derivative of the term “quilombos,” which refers to the communities of escaped slaves in Brazil from the early 16th century to 1888. Similar communities with different names were found throughout the Americas: palenques, cimarrones, and maroons. Quilombismo, then, is an ideology based on an understanding of quilombos as historical beacons of democracy and equality. By offering an alternative to captivity, quilombos allowed Africans “to recover their liberty and human dignity” by organizing their own “viable free societies.”
Capoeira or the Dance of War by Johann Moritz Rugendas (1825). Source: Wikimedia Commons.
Quilombismo is also based on an unusually broad understanding of quilombos, one that encompasses more than just remote communities of escapees. Nascimento includes any Afro-Brazilian cultural organization that provided a means of building community and facilitating African continuities, even those that were tolerated (or even encouraged) by the authorities: lay Catholic brotherhoods and sisterhoods, terreiros, afochés, and samba schools. All were “genuine focal points of physical as well as cultural resistance.” They were legalized quilombos.
In this way of thinking, a quilombo is not a relic of history but an ongoing, adaptable product of present circumstances. A quilombo is a model that “has remained active as an idea-force, a source of energy inspiring models of dynamic organization.” It is a heroic prototype of African-American liberatory activism, in a constant process of “revitalization and remodernization.”
Nascimento was an adamant pan-Africanist who believed that “black people have a collective project: the erection of a society founded on justice, equality and respect for all human beings; a society whose intrinsic nature makes economic or racial exploitation impossible.” Quilombismo is thus both a black movement and a humanist ideology.
It is African and universal, Brazilian and international. It is rests on the culture and struggle of black men and women around the world. It is radical in its call for communitarianism and its rejection of capitalism. It aims for the liberation of all human beings, sustaining “a radical solidarity with all peoples of the world who struggle against exploitation, oppression and poverty, as well as inequalities motivated by race, color, religion or ideology.”
This is a brilliant call to arms, a moving and powerful ideology of cultural reclamation, resistance, and transfiguration. It is a revolutionary manifesto, bold and unafraid, particular in its details and universal in its goals. It is vitally relevant to today’s struggles for full and equal humanity.
It is also flawed.
Quilombismo does not stand up to historical scrutiny. There are problems with the historicity of Nascimento’s ideology. For example, some of Nascimento’s premises about about black antiquity, pre-Columbian Afro-America, and Afro-Brazilian history have not held up. Scholars have largely rejected notions that Africans were present in the Americas long before Europeans arrived. Afro-Brazilians were not all, in fact, “literally expelled from the system of production as the country approached the ‘abolitionist’ date of May 13, 1888.” And the definition of favela is far more complicated than Nascimento’s simplistic description of “makeshift shanties of cardboard or sheet metal, perched precariously on steep, muddy hills or swamps” allows.
Then there is the most significant problem: that quilombismo is based on an idealized, mythical, ahistorical understanding of quilombos themselves. These communities of escaped slaves were not necessarily the bastions of freedom and communitarianism that Nascimento, like others in Brazil’s Black Movement, assumed (and continue to assume) them to be. Indeed, the largest, most iconic of them all—Palmares, a quilombo of twenty thousand people who resisted all state attempts to destroy it for nearly 100 years—was not an egalitarian society at all. It was hierarchical. It was organized not by democratic but by tributary and kinship relations, along modes of the Central African states from which many of its first residents originated.
Painting of a battle at Palmares. Image via Black Women of Brazil.
Painting of a battle at Palmares. Source: Black Women of Brazil.
Nor was it entirely black and entirely free. As Robert Nelson Anderson has argued, while many of the founding residents were born in Angola, over time Palmares became a multi-ethnic and largely creole community, with most palmarinos having been born in Brazil of African descent. The community included enslaved people, displaced Portuguese and Dutch colonists, and impoverished immigrants of various racial backgrounds. It was not only an alternative society for Africans and Afro-Brazilians; it was an alternative to the colonial state for any who wished to reject it.
So here we come face to face with what Africanist Luise White, in another context, has called the difference between historical fact and social truth. Quilombismo is an ideology based more on the myth of quilombos than on their historical realities. What we today believe Palmares to have been is not, in fact, what it was.
What do we do with this as scholars, teachers, writers and activists? How do we confront an ideology that is historically problematic at the same time that it is politically powerful?
I believe we can do this by not discrediting Nascimento’s vision. We can recognize its errors while celebrating its purpose. We acknowledge what is true and we challenge what is not. And we raise questions—useful, generative questions—about the ways in which history is used for political purposes, by whom, and how. Indeed, one of the most fascinating aspects of his groundbreaking ideology is that it celebrates a history that is more legend than fact and that yet, in spite of this, is a significant and powerful history.
Nascimento’s agenda was nationalist, pan-Africanist, and humanist. His sense of responsibility was for “the destinies and futures of the Black Africanist nation worldwide.” He used his understanding of history to advance his goals, imperfect though that understanding was. In considering his work, we can be both admiring and critical. We can use history to both interrogate and respect his ideas. Teaching “Quilombismo” is one way, at this critical moment, to support our students’ activism while also sharpening their acumen.
Laura Premack is a historian of Latin America and West Africa and an interdisciplinary scholar of religion, culture, and globalization. She is currently Assistant Professor of Latin American History at Keene State College. She is working on a book manuscript entitled, Atlantic Demonologies: A Spiritual Cartography. Follow her on Twitter @LauraPremack.
Comments on “Teaching Quilombismo: An Afro-Brazilian Political Philosophy
• Intellectual warfare- Dr. Carrutherts is right on point.
• There’s a significant contrast between myth and reality about the early American colonies and establishment of the country. It’s time we looked more carefully at that as well!!
Comments are closed.
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How did Mississippi get its name?
Quick Answer
According to the Encyclopædia Britannica, Mississippi's name was derived from a Native American language. The Online Etymology Dictionary explains that the name was originally that of the river. The name combines the Ojibwa words "mshi," meaning "big," and "ziibi," meaning "river."
Continue Reading
How did Mississippi get its name?
Credit: Stuart Seeger CC-BY 2.0
Full Answer
Mississippi is one of the smaller states in the United States. It was first organized as a U.S. territory in 1798, then became the 20th state of the union when it achieved statehood in 1817. The state was historically known for a genteel, rural and relatively relaxed lifestyle. The old towns in the state feature a number of historic mansions that reflect this legacy.
Learn more about The South
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3 March
Sir George Simpson (1792-1860)
Simpson Circles World
Philanthropy is not the object of our visits to these Northern Indians.
George Simpson, 1821
One of the most colourful characters in Canadian history was Sir George Simpson, Governor of the Hudson's Bay Company. On March 3, 1841, he began a trip around the world that took twenty months.
Scottish-born, he was only thirty-three when the Hudson's Bay Company sent him in 1821 to govern what is now western Canada. The Hudson's Bay Company had just taken over its bitter rival, the Northwest Company, and a strong, wise leader was needed to blend the two together. Simpson virtually ruled western Canada for forty years.
Simpson was a fur-trader, not a farmer, but he tried to help the settlers in the Red River area by buying their surplus products. He even organized an experimental farm on the Assiniboine River and imported the best thoroughbred cattle and horses from Britain. Even so, late in his career, he told a special committee of the House of Commons in London that the soil in western Canada was useless for farming. He wanted to protect the area for fur trading.
Simpson made his trips across Canada by canoe. Traveling would begin every day at 3 a.m., after Simpson had had a swim, and continue almost without pause until dark. Colin Fraser, Simpson's piper, was always a member of his party. On approaching a settlement, Fraser would stand in the stern and play his bagpipes, while Simpson, wearing top hat, cloak, and gaiters, would stand erect in the bow.
On one trip in 1828, Simpson traveled from Hudson Bay to the mouth of the Fraser River in ninety days. This included paddling down the Fraser River itself, which Simon Fraser had done only twenty years before. It was one of the most dangerous journeys ever undertaken by man.
Simpson was not a Pacific coast fan. He thought that living in what is now British Columbia was unhealthy and would only allow his traders to stay there for two years, after which they had to go to Fort Garry (Winnipeg) to "recuperate."
3 March
-1722 France divided Canada into "parishes." 1838 Five hundred American sympathizers of the Canadian "rebellion" were repelled at Point Pelee, Lake Erie.
-1870 Thomas Scott was condemned to death after his trial at Fort Garry.
-1887 The United States passed the Fisheries Retaliation Act against Canada.
-1945 Canadian and American troops linked in Germany as Nazis retreated along the Rhine.
-1962 The death of Cairine Wilson, the first woman senator in Canada, was announced.
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Navigation Links
Increase in Cambodia's vultures gives hope to imperiled scavengers
Researchers report that record numbers of vultures have been counted in Cambodia's annual vulture census, with 296 birds of three species found at multiple sites across the Northern and Eastern Plains of Cambodia by the Cambodia Vulture Conservation Project, a partnership of conservationists led by the Wildlife Conservation Society.
The record count means that Cambodia is home to the only increasing population of vultures in Asia. Specifically, the census indicates that the country's population of white-rumped vultures is increasing; populations of red-headed and slender billed vultures were found to be stable. All three of Cambodia's vulture species are listed as "Critically Endangered" by the World Conservation Union (IUCN).
Vulture populations in Southeast Asia are primarily threatened by the declining number of large herbivores in the region, but have been largely unaffected by a far greater threat to Asia's vultures: the veterinary drug diclofenac. Widely used as an anti-inflammatory drug for cattle in South Asia, diclofenac is toxic to vultures, causing death through renal failure and visceral gout to birds that feed on the cattle carcasses and has led to global population declines higher than 99 percent in some vulture species.
The census success follows a record breeding season for vultures in Cambodia. This year, a total of 36 vulture chicks fledged from colonies across the north and east of the country, an increase from last year's total of 19 chicks.
Vulture conservation efforts in Cambodia are the result of a number of activities promoted by the Cambodia Vulture Conservation Project. For instance, vulture nests are protected by local community members who are paid a small fee for their support. This ensures that vulture nesting success is greatly improved and also benefits local community members who often have few other sources of income during the dry season, which coincides with the vulture breeding season. Vulture food sources are supplemented by 'vulture restaurants,' feeding stations that also give visitors the opportunity to see these huge birds up close.
"By protecting nests and supplementing food supplies, we are saving some of the world's largest and most charismatic birds," stated Dr. Hugo Rainey, WCS technical advisor to the Cambodia Vulture Conservation Project. "Nowhere else in Asia do vultures have such a promising future."
While conservationists can point to recent successes in the conservation of Cambodia's vultures, they also warn of the rising threat of agricultural pesticides to the birds. Since December 2008, more than 20 vultures are known to have died from consuming domestic animals that had been poisoned accidentally by the inappropriate use of pesticides. This practice may also present a risk to human health.
Song Chansocheat, Ministry of Environment and WCS Vulture Project Manager, commented that "Cambodia is the only Asian country where diclofenac is rarely used and vulture populations are managed. We have been monitoring vultures since 2004 and there have been increasing numbers of poisoned birds recently. Educating people about the risk to wildlife and people from incorrect use of poisons is important."
"Cambodia has become a critical source site for vultures, one that we need to protect as a means of saving these ecologically valuable birds," said Joe Walston, director of the Wildlife Conservation Society's Asia Program.
Contact: John Delaney
Wildlife Conservation Society
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Illustrated Dictionary of British Churches
History and Architecture
A rebus is a visual pun, a pictogram, or play on words, usually in the form of a painting or carving that illustrates a family name. Rebuses are often found on medieval tombs where they depict in a visual manner the family name of the deceased. They are also often found as decorative elements (such as a roof boss) remembering an important church patron. Rebus principles are frequently used in heraldry, where the pictogram practise is called canting. A commonly used symbol in rebuses was a barrel, which in the medieval period was known as a tun. Thus a barrel symbol could be used to represent the last part of a name like Bolton (Bolt + tun).
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What Is the Water Cycle?
Let’s Get Started
Scientist often use models, which can have many different functions. Models frequently are used to explain difficult concepts and to make concepts more tangible. Scientists also use models to make and test predictions.
In this activity, students will create and observe a simple model of the water cycle, predict the behavior of the model, draw and label the model, and draw conclusions from their experience. The model can be built from a clear plastic shoe box or storage box, or from a cardboard shoe box lined with aluminum foil or plastic wrap. To line the shoebox, press a single sheet of aluminum foil or plastic along the bottom and up the sides of the box. Do not cover the top of the box with foil for the original investigation (you may wish to allow students to design different models later, in which they may decide to cover the top of the box with something like aluminum foil.)
Discuss the model with the class. Ask, Which part of the box and its contents could represent land? Which part could represent snow or ice on the top of a mountain? After students have constructed the model, ask them to predict what will happen inside of the shoe box once it is placed in a sunny spot. If a window is not available, you can place the box under a lamp with an incandescent bulb. Make sure the box is close enough to receive the bulb’s heat, but not close enough to melt or burn the plastic.
Tell students to fold a piece of paper in half, hamburger style (paper should go from being 8 ½” by 11” to 8 ½” by 5 ½”), and draw a side view of what their prediction would look like on the top half of the folded paper. Have students periodically observe their boxes over several hours. After several hours, ask each student to record what the box looks like on the bottom half of his or her sheet.
Funded by the following grant(s)
National Institute of Environmental Health Sciences, NIH
National Institute of Environmental Health Sciences, NIH
The Environment as a Context for Opportunities in Schools
Grant Numbers: 5R25ES010698, R25ES06932
Houston Endowment Inc.
Houston Endowment Inc.
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Create your own at Storyboard That Mercutio and Benvolio are on their way home. Benvolio knows that the tempers are high and begs Mercutio to go home. Mercutio on the other hand is ready to fight. The Capulets and Tybalt enter in search of Romeo. Romeo has recently gained a reason to love the Capulets and will not fight. Mercutio will not let them abuse Romeo though. Mercutio and Tybalt fight, and Mercutio dies. Romeo, filled with grief feels that he is to blame for the death and will not leave unless either him or Tybalt dies. Tybalt feels confident and takes Romeo up on the offer. He is ready to kill whoever. Romeo kills Tybalt. The Capulets are distraught. Benvolio helps Romeo realize how much trouble he will get in if he stays there and Romeo begins to flee the scene. The Prince arrives and sees the mess that has happened. He declares that Romeo's punishment is to be banned from Verona. This scene also demonstrates the literary term, monologue. A monologue is a long speech by one character. Here it is seen that Benvolio has begun explaining the incident, and is continuing to talk for a long time. This is an example of a monologue. Tybalt was the one who started the fight before he was killed... Can we please go home?? Never! If we have to fight that is what we do. Where is Romeo? Do not fight this weak man, fight me There really is no reason to fight How did I let this happen... My nephew, my nephew!! Romeo you have to leave Romeo is banned from Verona! You will die with him!
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Adjective "Lower" definition and examples
Definitions and examples
Less high in position.
1. 'Resuscitation may have dislodged it and allowed minute food particles to pass into the lower respiratory tract.'
2. 'managers lower down the hierarchy'
Denoting an older (and hence usually deeper) part of a stratigraphic division or archaeological deposit or the period in which it was formed or deposited.
1. 'Lower Palaeolithic'
Situated to the south.
In or into a lower position.
Move (someone or something) in a downward direction.
1. 'He turned to tap on his laptop and a plasma screen lowered from the ceiling.'
2. 'He lowered his hand, moving his focus to the paints and pencils and brushes that had been forgotten for so long.'
3. 'He gently lowered his head and rested it on the cold glass.'
4. 'The first panel had been lowered into place and was being anchored.'
5. 'Mona stood still as the casket was lowered slowly into the ground.'
6. 'Mules, lowered by rope down the narrow shaft into the mine, were used in the early mining operations.'
7. 'A mere glance upwards at a bright lamp caused it to lower from the domed ceiling.'
8. 'Amidst the drizzle and the strong winds, the box was lowered into the water.'
9. 'Upon the third ring, my other hand released his and I lowered my fist, moving away from the elder man and back to my laptop.'
10. 'The eagle touched down, and the platform slowly lowered down to the ground.'
11. with object 'traffic speeds must be lowered'
12. no object 'temperatures lowered'
13. 'The Fed lowered its overnight bank lending rate to 1.25 percent, the lowest since 1961, in November.'
14. 'Her voice lowered to a substantial degree, as if she spoke of something resentful.'
15. 'Stronger signals, reduction in congestion and lowering the drop call rate are on the agenda.'
16. 'Cost is still an important part of the equation, but technology can lower costs without any need to move offshore.'
17. 'The temperature can gradually be lowered but should never be allowed to fall below 45 degrees.'
18. 'The announcement regarding the move to lower its debt is expected to be accompanied by confirmation that it is to make job cuts across the group to cut costs.'
19. 'A tear glimmered and her voice lowered to a mere whisper.'
20. 'Workers initially demanded a 24 percent wage increase which union officials lowered to 20 percent.'
21. 'The problem isn't merely that standards must be lowered in order for the weaker students to pass.'
22. 'That is something the Executive has refused to do, on the grounds it would lower esteem for children from broken homes.'
23. 'But does it not say something if they are still trying to get more money by lowering themselves to prostitution?'
24. 'You have lowered yourself to an extent I didn't think was conceivable.'
25. 'He lowers himself and the book by covering these topics.'
26. 'And so what if the media have lowered themselves to airing snuff films in an effort to boost ratings?'
27. 'Apparently that friend saw Lindt's photo on my blog and felt Lindt was lowering himself to be associated with a empty vessel like myself.'
4. to make less loud: Please lower your voice.
5. to bring down in rank or estimation; degrade; humble; abase (oneself), as by some sacrifice of self-respect or dignity: His bad actions lowered him in my eyes.
6. Music. to make lower in pitch; flatten.
7. Phonetics. to alter the
More examples(as adjective)
"seas can be lower."
"places can be lower."
"offers can be lower."
"occasions can be lower."
"numbers can be lower."
More examples++
lower the boom on
lower the tone
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What is the rising action in the play "Trifles" by Susan Glaspell?
Expert Answers
bmadnick eNotes educator| Certified Educator
The plot of any piece of literature consists of the exposition, rising action, climax, falling action, and denouement. The exposition offers background information and an introduction to the characters and conflicts. The rising action is the complication of the events, where the conflicts become more involved. The climax is the most intense moment of the story, and the falling action is what happens after the climax. Denouement ties up any loose ends and clarifies any events.
The climax of this story is when the two women find the dead bird and realize that John Wright had broken its neck, taking away from Minnie the only joy she had in her sad life. The exposition starts at the beginning of the play, giving us the background of how John Wright's body was discovered and how they found Minnie sitting in her rocking chair. The rising action begins when the men go to look for "important" clues upstairs, leaving the two women in the kitchen.
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The Full Wiki
Vascones: Wikis
From Wikipedia, the free encyclopedia
Location of the tribe of the Vascones.
·Red: pre-Indoeuropean tribes
·Blue: Celtic tribes
Coins of King Arsaos, Navarre, 150-100 BCE, showing Roman stylistic influence. British Museum.
The Vascones (Latin, singular vasco[1][2]) were an ancient people who, at the arrival of the Romans, inhabited the region of present day Navarre, Lower La Rioja and north-western Aragon. It is likely that they are ancestors of the present-day Basques, to whom they left their name.
Roman period
Unlike the Aquitanians or Cantabrians, the Vascones seemed to have negotiated their status in the Roman Empire. In the Sertorian War, Pompey established his headquarters in their territory, founding Pompaelo. Romanization was rather intense in the area known as Ager Vasconum (the Ebro valley) but limited in the mountainous Saltus, where evidence of Roman civilization appears only in mining places, like Oiasso. The territory was also important for Romans as a communication knot between northern Hispania and southwestern Gallia.
The Vasconian area presents indications of upheaval (burnt villas, an abundance of mints to pay the garrisons) during the 4th and 5th centuries that have been linked by many historians to the Bagaudae rebellions against feudalization. By this time, it was already impossible to differentiate between the tribal Vascones and the rest of the Basque-speaking peoples, collectively called Vascones.
Early Middle Ages
In the year 407, Vascon troops fought on the orders of Roman commanders Didimus and Verinianus, repelling an attack by Vandals, Alans and Suebi. In 409, the passage of the Germans and Sarmatians toward Hispania went unhindered. The Roman reaction to this invasion and Vascon unrest was to give Aquitania and Tarraconensis to the Visigoths, in return for their services as allies by treaty (foederati). The Visigoths soon managed to expel the Vandals to Africa.
In the seventh and eighth century the island of Oléron, along with , formed the Vacetae Insulae or Vacetian Islands, according to the Cosmographia.[3] The Vaceti were the Vasconese by another name.
The independent Vascones stabilised their first polity under the Merovingian Franks: the Duchy of Vasconia, whose borders to the south remained unclear. This duchy would eventually become Gascony. After the Muslim invasions and the re-incorporation of Gascony to the Frankish Kingdom under Charles Martel, the territory south of the Pyrenees was reorganized around Pamplona. When Charlemagne destroyed the walls of this city after a failed attempt to conquest Zaragoza, the Vascons annihilated his rearguard in the Battle of Roncevaux Pass (778). Some decades later the Kingdom of Pamplona was founded.
1. ^ Gascon in the Online Etymology Dictionary.
2. ^ Vasco - Historia in the Spanish-language Auñamendi Encyclopedia.
3. ^ Collins, 214.
• Collins, Roger. "The Vaccaei, the Vaceti, and the rise of Vasconia." Studia Historica VI. Salamanca, 1988. Reprinted in Roger Collins, Law, Culture and Regionalism in Early Medieval Spain. Variorum, 1992. ISBN 0 86078 308 1.
• Sorauren, Mikel. Historia de Navarra, el Estado Vasco. Pamiela Ed., 1998. ISBN 84-7681-299-X.
See also
External links
• Vascones in the Auñamendi Encyclopedia, by Bernardo Estornés Lasa.
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Lab 6: Splicing Sounds
The objectives of this lab are to become familiar with using loops, ranges, and sample values to manipulate sounds, and to learn how to splice sounds together.
Splicing sounds is similar to copying and cropping pictures. You may want to have a copy of your copyInto function for pictures available for reference (or see Lab 3).
1. When we copied a picture into a new canvas, we passed the picture, the canvas, and the starting x- and y- coordinates of where to start copying on the canvas as parameters to the copyInto function. Next we looked at how much space was available to copy into, and checked whether or not that was enough room for the entire picture. We then copied as much of the original picture as we could onto the canvas. We can do something similar to copy a sound onto a new "tape", by passing in the sound, the tape, and the index of where to start copying onto the tape as parameters. We should determine how much space is left on the tape, and copy only as much of the sound as will fit onto the tape.
Write a function called copySoundInto which takes a sound, a tape, and a starting index as parameters. It should compute the space left on the tape beginning from the starting index, and then determine the minimum of the length of the sound and the space on the tape. It should then copy as much of the original sound as it can onto the tape. As with our copyInto function, we will not modify either of the sounds that are passed in as parameters. Instead we will make a duplicate of the "tape", copy our sound into the duplicate, and return modified duplicate at the end of the function.
2. You can make empty sounds by using the makeEmptySoundBySeconds function, which takes a time in seconds as a parameter. So, to execute your copySoundInto function, you could execute the following sequence of commands in the command area:
>>sound = makeSound(pickAFile())
>>newSound = makeEmptySoundBySeconds(5)
>>newSound = copySoundInto(sound, newSound, 0)
Try copying different sounds onto different length empty sounds at different positions, and see what happens. Try copying multiple sounds onto the same tape at different positions.
3. Write a new version of your copySoundInto function, copySoundIntoAtSec, that takes as a parameter the number of seconds into the tape to start copying, instead of the number of samples. You can accomplish this by converting the desired number of seconds to the corresponding number of samples, and then making a call to copySoundInto. The function getSamplingRate will be helpful for making the conversion. Keep in mind that getSamplingRate returns a real number, not an integer. That means that any value derived from the sampling rate will need to be converted to an integer using the int function before it can be used as an index value.
Reversing and Splicing
1. In the Sound Manipulations reading, there is a function to reverse a sound. That function is repeated here. Copy this code and test it with several different sounds. Does it work like you think it should?
def reverse(sound):
# create a new empty sound with same # of samples and
# sampling rate as the original sound
newSound = makeEmptySound(getNumSamples(sound),int(getSamplingRate(sound)))
# set up index to start at end of new sound
newIndex = getNumSamples(newSound) - 1
# loop through original sound, setting
# values in new sound
for index in range(getNumSamples(sound)):
value = getSampleValueAt(sound, index)
setSampleValueAt(newSound, newIndex, value)
newIndex = newIndex - 1
# return the new sound
return newSound
2. Write a new function, forwardAndReverse, that creates a new sound. The first half of this sound is an original sound. The second half of this sound is the original sound in reverse. The function should take a sound as a parameter, then create a new, empty sound, with the appropriate length and sampling rate. It will need to call on the reverse function to get the reversed version of the original sound, and then copy the two sounds into the new, empty sound at the appropriate locations.
3. Test your function with several different sounds to be sure it is working correctly.
4. Save one of your sounds created by the forwardAndReverse function.
Submit your results
1. Submit the file you created in this lab via .
Post your results
1. Create a new Lab 6 web page to include links for the new sounds that you created. You should include links to all original sounds you used as well as the new sounds. (You should have a new sound created from the splicing section of the lab as well as from the reversing and splicing section.)
2. Copy your web page and all the sound (.wav) files that should be on it to your personal web space on
3. Include a link to your new Lab 6 web page from your course page. Bring up your course page in a web browser and test your link.
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. .
Upper School ESL Workshop: Unit 3 Slide 5 of 8
Presenter: Paul Shoebottom
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Task embedding
Assume, as an example, that students are given a transcript of the Martin Luther King "I have a dream" speech and their homework assignment is to paraphrase part of it. Here are some classroom strategies that could be used to embed (scaffold) the task:
More on Scaffolding
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"url": "http://esl.fis.edu/teachers/fis/workshop/w3_5-8.htm"
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This week in history: August 10-16
10 August 2015
25 years ago: Magellan probe reaches orbit of Venus
Part of Venus' Eistla Regio displayed in three-dimensional perspective view
On August 10, 1990, the NASA spacecraft Magellan fired its solid-rocket motor to complete its 15-month journey from Earth and position it for an orbit of Venus. Magellan was the first US planetary spacecraft launched since 1978 and its successful maneuvering into orbit around Venus was a significant event for NASA after the problems in the Hubble mission earlier in the year.
George Alexander, chief spokesman for NASA’s Jet Propulsion Laboratory in Pasadena, said, “The system worked as planned. A lot of hard work was rewarded. I’m tremendously gratified we were able to do something for NASA and the public that shows this is a capable agency. This breaks the string of bad luck.”
As the spacecraft sped over the north pole of Venus, the braking rocket fired to slow it from a speed of 24,600 miles per hour to 18,500 miles per hour, allowing Magellan to be captured by the planet’s gravity. The mission plan was to map the surface of Venus with more accuracy than any previous probes, using cloud-piercing radar to produce photo-like images that could help answer the question of what caused Venus to become a 900-degree inferno—believed to be due to an unchecked greenhouse effect.
The radar mapping was scheduled to begin within a month of Magellan’s achieving Venus orbit. At its lowest point in orbit, the craft would reach 186 miles above the planet’s surface.
50 years ago: Watts riot in Los Angeles
California National Guard in Watts
On August 11, 1965, one of the largest urban uprisings in US history erupted in the Watts ghetto of southeast Los Angeles, beginning a week of fighting with police and National Guard troops that left 36 people dead, 1,000 injured, 4,000 arrested and $200 million in buildings and other property destroyed. More than 15,000 troops and 1,000 police were mobilized to subdue the uprising, ravaging a 50-square-mile area.
The riot was sparked by the arrest of a young black motorist, an incident that escalated into a roadside argument. But the cause lay in the appalling conditions of economic deprivation and racial oppression in the Watts ghetto, where more than 100,000 people lived crammed into a relatively small area, many living in run-down housing projects. The unemployment rate in Watts was 30 percent and half the population was on welfare, under conditions where the US economy overall was at the height of the postwar boom.
President Lyndon Johnson denounced the rioters, claiming that black youth who took up arms against the racist LA cops were morally equivalent to the Ku Klux Klan. All the officially recognized black civil rights leaders, from Roy Wilkins to Martin Luther King Jr., condemned the uprising and supported Johnson’s decision to send in the troops.
King travelled to Los Angeles and announced he would tour Watts to “offer hope to the ghetto.” But he was literally jeered out of Watts by youth who mocked him with chants of “I had a dream, I had a dream.” One onlooker commented, “Hell, we don’t need no damn dreams. We want jobs.”
The American Trotskyists, then organized in the American Committee for the Fourth International, the predecessor of the Workers League and the Socialist Equality Party, wrote, “[T]his insurrection has certainly struck fear in the hearts of America’s rulers who know full well that in order to save their dying system they will have to face and subdue bigger, better organized and more conscious rebellions in the future.”
75 years ago: The Battle of Britain begins
London street after air raid
On August 13, 1940, the German Luftwaffe launched a massive air attack with the aim of destroying the Royal Air Force (RAF) and wiping out Britain as a base of operations against Nazi Germany’s domination of the European continent.
The Luftwaffe first bombed airports, military-industrial plants and dock areas. Later, the bombing was extended to residential areas. On September 7 and 8 alone, 842 civilians were killed in mass bombings by the Luftwaffe on London. Britain retaliated by sending the RAF on missions to bomb Berlin.
Relying on their ability to decipher the German codes and the use of radar, British military commanders were able to parcel out fighter planes at precise locations to more effectively combat the German attack. From July to the end of October, the Luftwaffe lost 1,733 aircraft, while the RAF lost 915 fighter planes. In November the Luftwaffe ended daytime bombing and limited itself to night raids on the cities, industrial centers and ports. These missions continued until May 1941.
The German air raids were to have been a preliminary to an invasion by ground troops across the English Channel. But the dangers involved in such a massive seaborne operation, along with the inability to destroy the RAF, caused Hitler to postpone the invasion. More and more the military stalemate caused Hitler to relinquish the idea of decisively defeating Britain and turn instead to his main objective—the military annihilation of the Soviet Union.
The whole purpose of Hitler’s westward invasion of France and the Low Countries had been to free his hand for expansion into Eastern Europe and the USSR. After the collapse and surrender of France, Hitler had hoped that Churchill and the British bourgeoisie would come to terms with him and take part in a joint war on the Soviet Union. It was Churchill’s rejection of such an alliance that led to the German air assault.
100 years ago: Leading young physicist killed in First World War
On August 10, 1915, British scientist Henry G.J. Moseley was killed in the fighting on the Gallipoli peninsula against the Ottoman Empire in World War I. Moseley was 27 years old when he died. He was considered an outstanding young physicist and was responsible for Moseley’s Law in X-ray spectra.
Through the use of X-ray spectroscopy Moseley discovered a relationship between the wavelengths of the X-rays produced and the atomic numbers of the metals that were used as targets in the X-ray tubes. His work provided the explanation from physical laws of the previous empirical and chemical concept of atomic number, sorting the chemical elements of the periodic table in a logical order based on their physical characteristics. It also advanced atomic physics by providing the first experimental evidence in favor of the Rutherford-Bohr model of the atom as a small positively charged nucleus surrounded by electrons travelling in circular orbits.
In the opinion of some scientists, Moseley, had he lived, could have contributed much to our knowledge of atomic structure. Bohr said in 1962, “You see actually the Rutherford work [the nuclear atom] was not taken seriously. We cannot understand today, but it was not taken seriously at all. There was no mention of it any place. The great change came from Moseley.”
The First World War was a catastrophe for the working class. It also had a devastating impact on the development of science and culture. Of the young people who matriculated to Oxford between 1910 and 1914, almost 30 percent were killed during the war. These figures were not unique to Oxford or indeed to Britain. Young scientists, writers, artists from every country were killed in combat and from disease in the trenches before they had the chance to develop or fully use their talents.
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Arnold's Tristram and Iseult
A key question we should ask about Tristram and Iseult is why Arnold uses this medieval legend. Remember the beginning of the biography on Arnold: "How is a full and enjoyable life to be lived in a modern industrial society?"
As we saw in the Switzerland poems (see the NA), Arnold has serious doubt about the nature of love, about the tension between real and imagined love as well as love that cannot be realized in a world that is isolating, lonely, and full of despair. The Tristram legend offers Arnold a way of exploring these ideas since it captures them in a dramatic and haunting manner. Review the key lines about love in Part III of the poem (lines 112-42). Note that Arnold does not judge the lovers in this poem.
Chivalry is also important in the poem. It shows Tristram as being worthy of belonging to King Arthur's court. The chivlaric code would prevent Tristram from acting on his passion and love for Iseult, but the love philter counteracts this code. But it also possible to argue the poem exposes the limits of chivalry since Tristram and Iseult's love transcends the code of chivlary and morality of marriage convention. (Compare this to Scott's Ivanhoe.)
For Arnold, the past offers a commentary on the present. Think about what this specific commentary is.
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"url": "https://www4.uwsp.edu/english/rsirabia/notes/383/victorianMedievalism/Arnold'sTristram.aspx"
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|
Meiji Restoration
related topics
{war, force, army}
{theory, work, human}
{government, party, election}
{country, population, people}
{son, year, death}
{church, century, christian}
{land, century, early}
{day, year, event}
{town, population, incorporate}
The Meiji Emperor,
moving from Kyoto to Tokyo, end of 1868.
The Meiji Restoration (明治維新 Meiji Ishin?), also known as the Meiji Ishin, Revolution or Renewal, was a chain of events that restored imperial rule to Japan in 1868. The Restoration led to enormous changes in Japan's political and social structure, and spanned both the late Edo period (often called Late Tokugawa shogunate) and the beginning of the Meiji period.
Full article ▸
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"language": "en",
"language_score": 0.812255322933197,
"url": "https://www.princeton.edu/~achaney/tmve/wiki100k/docs/Meiji_Restoration.html"
}
|
The Heiltsuk are Indigenous people who traditionally occupied a part of the central coast of BC in the vicinity of Milbanke Sound and Fisher Channel. They have been referred to also as the Bella Bella, a term anglicized from the name of a site located near the present-day community of the same name. The Heiltsuk speak Hailhzaqvla, a Wakashan language shared also with the Haihais or Klemtu (see Indigenous Languages in Canada).
Heiltsuk traditional territory.
(courtesy Victor Temprano/
Community Life
There were at least five bands of Heiltsuk, each associated with a particular territory, and each possessing its own winter village, head chief, ceremonial prerogatives and dialect. Unlike the First Nations to the north, the Heiltsuk, along with their neighbours to the south, traced their descent bilaterally, acquiring rights and membership in a particular group from either parent. Additionally, there were crest groups based on descent, similar to the clans of their northern neighbours. The crest groups were ranked, with raven being the highest, followed by eagle, killer whale (orca) and wolf. Each of these crest groups was represented in each Heiltsuk Nation. One of the obligations of the crest group was to perform memorial duties; such tasks went to the group associated with the father of the deceased.
Social Relations
Heiltsuk society was stratified into a hierarchy of five groups of people: head chief, chief, noble, commoner and low-class person. The upper classes maintained their status through the potlatch and ceremonial system in which chiefs called upon the resources of others to host dances and feasts. At these gatherings, hereditary prerogatives were displayed and such rights were validated within and beyond Heiltsuk society.
The traditional Heiltsuk economy focused on the harvesting and preservation of wild fish, birds, land and sea mammals, marine invertebrates and plants; there were no domesticated plants or animals. In late winter, Heiltsuk families left the central winter villages and set out for annually occupied seasonal camps where food was prepared for storage, to be used during the winter ceremonial season. Movement between camps was geared to the availability of resources. What was not available locally was traded for with for other Native people. Marine resources were exchanged via the Heiltsuk with more interior communities such as the Nuxalk and the Dakelh.
Housing and Travel
Winter villages consisted of large cedar plank houses with gabled rooves, double ridgepoles and carved interior posts. Bark houses were sometimes situated at camping sites. Travel was mostly by cedar bark canoes distinctively designed for use in open ocean or lakes. The Heiltsuk also excelled in other woodworking skills including the manufacturing of bentwood boxes and chests.
Colonial History
First contact with Europeans likely occurred in the 1780s, although trade with the Heiltsuk did not become common for another decade. In the early 1800s, the Heiltsuk were active participants in the maritime fur trade. In 1833, the Hudson's Bay Company established Fort McLoughlin on Campbell Island. This depot was dependent upon receiving furs obtained by the Heiltsuk through trade. The post closed in 1843, as the company's steamship Beaver provided an expedient means of collecting furs, and thus made the fort obsolete.
After the mid-1800s, the remnants of Heiltsuk communities, severely reduced in population due to a series of epidemic diseases, amalgamated at McLoughlin Bay. By the 1880s, the Heiltsuk population had decreased to around 200. In 1898, guided by Methodist missionaries, the population moved to the present-day site of Bella Bella.
Present Day
In the 20th century, Bella Bella expanded into a prosperous community focused on participation in commercial fishing, herring roe and forestry industries. Today, an active ceremonial life binds the communities with the traditions of their ancestors and the diverse Indigenous population who live along the west coast of British Columbia. Potlatches continue to mark significant points in Heiltsuk family life. In 1996, 1210 of the 2182 Heiltsuk members lived on-reserve in Bella Bella.
On 13 October 2016, a tugboat carrying more than 200,000 litres of diesel sank off the coast of Bella Bella, in the territorial waters of the Heiltsuk First Nation. An estimated 100,000 litres of fuel leaked into the water, affecting wildlife, the environment and the people’s food supply. On 6 November, federal transportation minister Marc Garneau met with Heiltsuk leaders and promised that a ban on oil tanker traffic on the North Coast of British Columbia is in the works.
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"url": "http://www.thecanadianencyclopedia.com/en/article/heiltsuk-bella-bella/"
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Natural disasters
What to do
1. Find 2 real examples. One has to be recent and the other very old.
2. Describe the disasters briefly (50 words) Use your own words. Don’t copy and paste.
3. Add some media. (videos and photos)
4. Make a list of at least 10 words related to that kind of disaster. (Write the definitions in English)
5. Write down 3 questions that you would ask to someone who has lived that disaster.
• Open a google doc to collect the material and discuss.
• Use a google spreadsheet to write down the vocabulary.
• Use a google presentation to finish your work.
• Title, example: VolcanoABF
• Move everything to the folder Disasters>Volcanoes, etc
• Remember to include the sources: the exact url you got the information from.
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"edu_score": 3.6875,
"fasttext_score": 0.9920431971549988,
"language": "en",
"language_score": 0.883764922618866,
"url": "http://takeitfurther.wikispaces.com/Natural+disasters?responseToken=0d50f76329a2d1f407f2cd9ca35db8daa"
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Notes on the history of language
1 basic notes
2. glottochronology controversy -- How old is PIE? IE sound change correspondences.
3. The family of IndoEuropean languages
4. the Rosetta stone - history and analogy to language acquisition
5. children and language change -- the development of modern English
6. Expanded older notes.
7. overview of language evolution stages , timeline for everything
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"edu_score": 3.546875,
"fasttext_score": 1.0000056028366089,
"language": "en",
"language_score": 0.7285463213920593,
"url": "http://pubpages.unh.edu/~jel/712/history/history_index.html"
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Mirages in the Desert
(Click on the images to enlarge)
Gaspard Monge
Gaspard Monge from Louis Reybaud, Histoire de l’expédition française en Égypte (Paris 1830-36) v. 6.
Gaspard Monge, a mathematician, was one of the leading members of the French scientific contingent. Already in his fifties at the time of the Egyptian expedition, Monge was a highly regarded professor, administrator, and theoretician who was known particularly for his work in descriptive geometry.
As a close friend of Napoleon, and as first president of the Institute, he should have busied himself with carrying out Napoleon’s suggested research programs. Instead, Monge became fascinated with the physics of mirages. The phenomenon became known to the French army quite early, when they marched across the desert from Alexandria to Cairo. The soldiers saw what seemed to be immense lakes in the distance. A distant village might appear as if it were an island, surrounded by a lake with the inverted image of the village reflecting off its surface.
Exhausted by heat and fatigue, they saw the inviting and large body of water retreat as they gradually approached until it finally disappeared altogether, to their great disappointment. The same vision would then repeat itself further on, again and again. Knowledge of the mirage effect was not new, as there are numerous reports and descriptions in the scientific literature and in the writings of antiquity, such as that of Diodorus. No one before Monge, however, had tried to give an optical explanation for mirages.
Pyramids and sphinx at Giza A mirage in the desert
Pyramids and sphinx at Giza from Description de l’Égypte Antiquités, v. 5. A mirage in the desert, from Camille Flammarion, L'Atmosphere (Paris, 1873).
Monge’s interpretation was that light rays were bent by the layer of superheated air just above the sand. Heat radiating from the desert’s surface warms the air immediately above it and reduces the air density. The boundary between this heated layer of air and the layer of cooler, denser air above it acts as a lens, bending or refracting the light rays from the sky back upward toward the cooler layer and thus toward the eyes of the observer. The mirage image seems to come along a straight path that originates from the ground, giving the appearance of a layer of water at the surface. The greater the temperature difference, the greater will be the effect of the mirage.
Monge’s paper explaining the phenomenon may be the most famous memoir contributed to the Institute of Egypt. It was published in the Mémoires sur l’Égypte in 1800, which gave it fairly wide exposure. Seventy years later it was still being cited by the popular scientific writer Camille Flammarion who wrote, perhaps with a bit of national pride, that it was Monge who had succeeded in giving an explanation to the mirages that had surprised and puzzled all the other observers.
^ Back to the Top
Related Links
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"url": "http://napoleon.lindahall.org/mirages.shtml"
}
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23 Following
Parrish Lantern's Casebook
The Art of Haiku: Its History through Poems and Paintings by Japanese Masters - Stephen Addiss To most people haiku is a three line poem, following a 5-7-5 syllable formula, but Stephen Addiss argues that this does no more than prick the surface of this fascinating poetic form. He goes on to state that, rather than constrain with rigid definitions, it may be more useful to discuss guidelines that the majority of haiku follow. Haiku in Japan are generally written or printed in a single column. Nevertheless, until the twentieth century, most traditional Japanese haiku fell into the 5-7-5 formula, although this wasn’t always adhered to by some of the great masters, when it suited their purpose to ignore it. Another reason that this syllable count often got ignored, was when haiku transcended the Japanese language, for example haiku written in English often have fewer than seventeen syllables because English is a more compact language than Japanese, this often is the case of haiku in other Languages.So if we take away the constraints of the 5-7-5 syllable count, what are the characteristics that we can use to define haiku? The obvious one is a closeness to the natural world, from which the poet tends to draw the majority of the images that the poem relies on to convey it’s meaning. This usually involves concrete observations, expressed briefly through the use of everyday language and syntax that is natural rather than poetic .garden in winter -the moon also becomes a threadin the insect’s song(Matsuo Basho 1644-94)Traditional haiku often include pause marks called kireji (cutting words), that serve to mark rhythmic divisions, as a kind of verbal punctuation mark, for example at the end of the first or second segment there may be an extra syllable such as ya, indicating a pause or signalling a moment of separation (change of theme or meaning). In fact you could state that kireji serve primarily as sonic punctuation or as intensifiers of mood and meaning and as they have, or seldom have, meaning are there purely to contribute rhythm and sounds. Many Japanese haiku can have fewer than seventeen (active) syllables. kanashisa ya tsuri no ito fuku aki no kazesadness -a fishing line blownin the autumn windYosa Buson (1716–1783) The third major characteristic of haiku are the seasonal references, the Kigo, the great majority of traditional haiku indicate a particular season, sometimes directly (as in the Basho poem above) or through a specific image that has come to signify a season for example:Spring (haru) Early spring: 4 February–5 March, Mid-spring: 6 March–4 April, Late spring: 5 April–5 May.Ume blossoms, Japanese bush warbler, Cherry blossoms, Frogs, Skylarks.Summer (natsu) Early summer: 6 May–5 June, Mid-summer: 6 June–6 July, Late summer: 7 July–7 August.Wisteria, Wild Orange blossoms, Iris, Lotus, Cicada, Little Cuckoo.Autumn (aki) Early autumn: 8 August–7 September, Mid-autumn: 8 September–7 October, Late autumn: 8 October–6 NovemberTyphoon, Thunder, Milky Way, Moon, Insects, Crickets, Nashi pear, peach, Coloured leaves, Scarecrow.Winter (fuyu) Early winter: 7 November–6 December, Mid-winter: 7 December–4 January, Late winter: 5 January–3 February.Cold, Fallen leaves, Snow-viewing (first snow), Ice, Owls, Ducks, bare trees. By the use of one of these specific images the poet suggests to the reader which season the poem is referring to, and as this adds to the mood and meaning of the haiku, these references are significant. This leads me perfectly on to the fourth and possibly most important element of haiku, a haiku suggests rather than defines its meaning, leaving the reader or listener to complete much of the process, to join the writer in the completion of the haiku, and as a haiku can have multiple meaning, this allows for individual interpretation as opposed to one concrete view.This is also helped by the brevity of the form, the fewer the words the more potential for multiple implications.This piece is merely a brief overview of the form that is haiku, which has become a worldwide phenomenon and yet is only one half of the story, haiga, the other half is almost unknown and yet as an art form was practised by all the great masters, Yosa Buson (1716–1783) was a talented painter, but even those with more modest skills such as Kobayashi Issa (1763–1827) created haiga esteemed by those that viewed them. In fact having too much technique can be seen as much a liability as having too little, since sincerity and suggestion matter more than obvious mastery and specificity. This aesthetic haiga shares with haiku, along with brevity, naturalness, and the idea of suggestion to create a bond with the viewer as they participate in the haiku/haiga creation.Japanese haiga, the word-image relationship developed into three main patterns/ forms.An informal portrait of poet with one of their haikuInteraction (most common)Text-image relationship.The first is the most simple and is normally just an informal picture of the poet with one of their haiku. This follows on from an earlier Japanese tradition of portraits of aristocratic tanka masters, although the brushwork in haiga portraits appear less sharp and precise and can seem close to caricature. The second haiga form, Interaction, supports the haiku and by this I mean that an image is represented in both words and painting, for example if the haiku mentions Ume blossoms an image of said blossoms will be in the picture, however in good haiga, the one is not there merely to represent the other, but to add to the overall effect, working in a kind of symbiosis, reinforcing and contributing to a multi-layered view of the work. The third form, the text-image relationship is the most intriguing of the three, in this the painted images and the words do not appear to have a direct relationship with the idea of adding further meanings to the poem and image creating a resonance that expands the overall expression.In The Art of Haiku, Stephen Addiss, one of the foremost experts on this art form traces the history of Japanese haiku, starting with the earlier poetic traditions from which it was born through to the twentieth century and its position as possibly one of the best known poetic forms in the world. His approach to this subject is to highlight the work of the leading masters such as Bashō, Buson, Issa and Shiki, and by focussing on “the Great Four” he uses these as points in history allowing him to highlight other fine but lesser known poets. In the process tracing the evolution of haiku from its roots in Tanka (Waka) from the earliest anthology, Man'yōshū (Collection of Ten Thousand Leaves, compiled 686 - 784) through to the modern era covering all the major names from both haiku and haiga, with the aim of demonstrating the relationship between the forms which were composed to “create a spontaneous interconnection with the readers who play a vital part in the expressive process.” and their development into the poetic form loved and admired the whole world over, with haiku societies in most nations on this planet.Stephen Addiss has created a wonderful and fascinating book that is part history, part poetry anthology, and part art book, presenting a cornucopia of examples in both poetry (original & translations) and painting. It was a pleasure reading this book, which although a thorough in-depth study of its subject matter, managed to be informative, instructive & educational without being dry and dull. If you have an interest in haiku, haiga, in Japanese history and culture, even if your interest is in the Japanese aesthetic of Wabi sabi, this book has something to offer and delight youI would like to add a proviso, I got this book through Netgalley, in an E-book format and although reading it was fine I didn’t feel it showed the art work to their best, so I would suggest that if you were to purchase this choose a physical copy and be in the admirable position of being able to read the haiku whilst viewing the haiga in all its glory, that is my only reservation as this is a book that I will be revisiting with pleasure and with the knowledge that I will learn more about what is a fascinating subject with each new visit.http://parrishlantern.blogspot.co.uk/2012/08/the-art-of-haiku.html
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|
In early times, people believed that the earth is flat. For centuries, men were
afraid to venture out too far, lest they should fall off the edge. Sir Francis
Drake was the first person who proved that the earth is spherical when he
sailed around it in 1597. Consider the following Qur’aanic verse regarding
the alternation of day and night: “Seest thou not that Allah merges Night
into Day And He merges Day into Night?” [Al-Qur’aan 31:29]
Merging here means that the night slowly and gradually changes to day and
vice versa. This phenomenon can only take place if the earth is spherical. If
the earth was flat, there would have been a sudden change from night to day
and from day to night.
The following verse also alludes to the spherical shape of the earth: “He created the heavens And the earth In true (proportions): He makes the
Night Overlap the Day, and the Day Overlap the Night.” [Al-Qur’aan 39:5]
The Arabic word used here is Kawwara meaning ‘to overlap’ or ‘to coil’– the
way a turban is wound around the head. The overlapping or coiling of the day
and night can only take place if the earth is spherical.
The earth is not exactly round like a ball, but geo-spherical i.e. it is flattened
at the poles. The following verse contains a description of the earth’s shape:
“And the earth, moreover, Hath He made egg shaped.”
[Al-Qur’aan 79:30]
The Arabic word for egg here is dahaha, which means an ostrich-egg. The
shape of an ostrich-egg resembles the geo-spherical shape of the earth. Thus
the Qur’aan correctly describes the shape of the earth, though the prevalent
notion when the Qur’aan was revealed was that the earth is flat.
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"url": "https://scienceworldandislam.wordpress.com/2017/02/09/the-spherical-shape-of-the-earth/"
}
|
Compare the meerkat call
“Alan! Alan! Alan!” Not only can small mammals respond to their name, but it has now been established that they are able to recognise calls specific to other individuals. Research has been conducted by Dr Simon Townsend on meerkats inhabiting the Kalahari Desert, South Africa. Dr. Townsend and his research team are the first scientists to discover that voice recognition occurs in other species apart from primates and also suggests the possibility of it being more wide spread in the animal kingdom than previously thought.
Although the research has produced interesting results, Dr. Townsend and his team had to overcome the problem of the meerkat’s reaction to an individual’s call. Although it is widely known that meerkats are social animals, it is much harder to distinguish the relationships to one another in a clan. Consequently, it is difficult to observe which individual will respond to whom. To solve this problem, audio playback was used to gauge the individual’s reaction to a call.
Recordings of staccato “close calls” (noises made to reassure other members of the clan they are there and as territory warnings) were played to an individual from one location and their response recorded. A call from the opposite orientation from which the original call came from was then played to the same meerkat and the response was once again recorded. In the final stages of the experiment, recordings from the same meerkat were played to one individual from conflicting directions.
Dr. Townsend commented this process as being a “violation of the animal’s expectation” as the meerkat making the call could not physically be in two places at the same time. Also, during these periods of “violation” the meerkats became more vigilant to their surroundings. It is possible the ability to recognise individual voices has evolved to make communication between members of the same clan more efficient due to meerkats having complex social groups.
It is hoped this research will inspire others to investigate whether other animals can also recognise individual calls and whether we have underestimated other mammals’ communication methods.
Check out Frontier’s blog for more cool articles!
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"language": "en",
"language_score": 0.9745690822601318,
"url": "https://haleydolton.wordpress.com/category/meerkat/"
}
|
Give an example of foreshadowing that clues the reader of what the ending of the story will be.
Expert Answers
jdslinky eNotes educator| Certified Educator
There are many examples of foreshadowing in "The Scarlet Ibis" by James Hurst. One example is the changing of what Doodle was called. His given name was William Armstrong; however, Brother (the narrator) renames him Doodle based on the way he appeared when he learned to crawl, "Crawling backward made him look like a doodle-bug..."(2). With this new name came less expectation: "because nobody expects much from someone called Doodle," foreshadowing the upcoming events.
Another example of foreshadowing is Doodle's request that Brother not leave him alone in the barn loft the day he is forced to touch his casket. Brother admits that this is a mean thing to do to his little brother, "and at times I was mean to Doodle," (3), and it foreshadows his behavior later in the story when Doodle is left behind in the storm. "When the deafening peal of thunder had died, and in the moment before the rain arrived, I hear Doodle, who had fallen behind cry out, "Brother, Brother, don't leave me! Don't leave me!" (9).
An additional example of foreshadowing includes Brother's statement about pride being "a wonderful, terrible thing, a seed that bears two vines, life and death," (4). This quote speaks to the fact that Brother only taught Doodle to walk because of his own pride. He was embarrassed by Doodle's inability to do things "normal" boys his age could do, so he set out to teach him. However, he pushed him too far in his attempt, which led to Doodle's untimely demise.
Furthermore, there are foreshadowing hints in the events that take place after Doodle learns to walk. The ibis' death is a strong clue because the ibis symbolizes Doodle. They are both weak, pushed beyond their limits, rare and beautiful. The ibis dies in a pool of red (feathers) under the bleeding tree, while Doodle dies in a pool of red (blood) under the red nightshade bush. Even their positions at death were similar: "Its long graceful neck jerked twice into an S, then straightened out, and the bird was still...Its legs were crossed and its clawlike feet were delicately curved at rest," (7) describes the ibis' position. Like the bird, Doodle "lay very awkwardly, with his head thrown far back, making his vermillion neck appear unusually long and slim. His little legs, bent sharply at the knees, had never before seemed so fragile, so thin," (9). Even Aunt Nicey's superstitious remark about dead birds, "Specially red dead birds," (8) being bad luck foreshadow an unhappy ending.
Lastly, Doodle's health worsens progressively throughout the process of his training: "Doodle suffered from one bad cold after another," (5). As Brother continues to push Doodle through the paces, "his face turned red and his eyes became glazed," (6), and eventually,..."Doodle began to look feverish...At night he didn't sleep well, and sometimes he had nightmares..." (7).
All of these examples point to the sad, preventable, yet eventual death of young Doodle.
Read the study guide:
The Scarlet Ibis
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Möbius strip
Show Summary Details
Quick Reference
A topological figure, named after the German astronomer, A. F. Möbius, made by putting a 180-degree twist in a long, rectangular strip, then pasting the ends together. The strip has only one surface and one edge. If a Möbius strip is cut longitudinally, it forms a double-sized ring. If a ring with a double twist is cut longitudinally, it forms interlocked rings. A Möbius strip demonstrates the behavior of a twisted ring chromosome when it attempts replication.
Subjects: Genetics and Genomics — Chemistry.
Reference entries
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"language": "en",
"language_score": 0.8394166827201843,
"url": "http://oxfordindex.oup.com/view/10.1093/oi/authority.20110803100202909"
}
|
Until the end of the 19th century, the Acadians lived in isolated groups and had little contact with the outside world. This isolation helped to preserve the traditions of their ancestors: their way of speaking (which is a variant from the Poitou region in France), their cuisine, their celebrations and their oral traditions. Since the Acadians’ arrival on the North American continent in the 17th century, they have passed down songs, stories and legends from generation to generation.
Before 1940, there were very few documents that illustrated Acadian folklore, and no real ethnographic research had been carried out. It wasn’t the 1950s that substantial collections of material were organized. Around 1970, with the establishment of the Centre d’études acadiennes (Centre for Acadian Studies) at the Université de Moncton, research into Acadian folklore began to flourish. Today, the “Acadian corpus” figures prominently in the intangible cultural heritage of North American francophones.
In 1685, Jean Campagna, a colonist who settled at Beaubassin, was formally accused of witchcraft. Documents related to the case constitute the first evidence of the popular beliefs in Acadia. In the second half of the 19th century, the newspaper Le Moniteur acadien published literary versions of tales and legends, but nothing touching on authentic oral tradition.
In 1877, the French historian François-Edme Rameau de Saint-Père published Une colonie féodale en Amérique (L’Acadie, 1604–1710) (A North American Feudal Colony: Acadia, 1604–1710). This work contained some information on the traditional life of the Acadians. A few years later, Philias-Frédéric Bourgeois conducted a survey of students at a school in Scoudouc, a village located about 15 kilometres northwest of Moncton, where the Virgin Mary had reportedly appeared. Much like present-day ethnographers, Bourgeois went to the village and interviewed witnesses. In 1896, Bourgeois published L’École aux apparitions mystérieuses (The School of Mysterious Apparitions), which recounted the experience. In 1911, André-Thaddée Bourque published Chez les anciens Acadiens (At Home with Ancestral Acadians), a work containing various details about the Acadians’ customs and popular beliefs.
Despite the efforts of a small number of authors and intellectuals, by the first quarter of the 20th century, no serious study of Acadian folklore had been conducted.
The Pioneers of the 1940s
Researchers began to approach the study of folklore with greater scientific rigour at the end of the 1930s and the beginning of the 1940s. At that time, the Notre-Dame de l’Assomption cathedral, the official monument of the “Acadian renaissance,” was built in Moncton. Between 1938 and 1941, there were 87 articles on Acadian popular songs published in the newspaper La Voix d’Évangéline. Writing in a periodical of which he was the assistant editor, Joseph-Thomas LeBlanc invited readers to send him versions of songs from the Acadian oral tradition and, thanks to this technique, he was able to collect more than 1,300 items. LeBlanc’s columns inspired the critical work undertaken by Marius Barbeau, including his Romancero du Canada (Ballads of Canada), published in 1937. By the time of his premature death in 1943, LeBlanc had become a recognized expert on Acadian folklore and had carried on lengthy correspondences with a large number of influential researchers.
Around the same time, in 1942, Father Anselme Chiasson and Father Daniel Boudreau produced the first volume of their Chansons d’Acadie (Songs of Acadia). This songbook quickly became popular. Many choirs and artists, in Acadia and Québec, drew on it for their repertoires. Eleven volumes of Chansons d’Acadie were published between 1942 and 1993.
In 1946, the French linguist Geneviève Massignon explored all parts of Acadia. As part of her doctoral studies, she researched regional speech and songs of the oral tradition.
The Golden Age
During the 1950s, Luc Lacourcière and Félix-Antoine Savard of Université Laval’s Archives de folklore carried out research into Acadia’s intangible heritage. Enthused by the richness of the Acadian oral tradition, they were able to generate significant collections of tales, legends and songs. Released in 1958, the album Acadie-Québec is one example from this extremely fertile period of collecting. Le Barachois, a collection of poems and reminiscences written by Savard, bears witness, from a literary perspective, to special moments spent among the Acadians.
Since 1966, the Université de Moncton has offered courses in folklore and, in 1970, the Centre d’études acadiennes was founded. Acadians themselves, with Father Anselme Chiasson at their head, quickly gathered folkloric material and created significant collections. Some of them, notably famous Acadians Édith Butler, Angèle Arsenault and Antonine Maillet, went to Québec with Lacourcière to pursue their studies.
During the 1970s and 80s, a considerable number of ethnologists crisscrossed Acadia enriching archival collections while writing scholarly articles, monographs and works on the subject of Acadian folklore. Among them were Catherine Jolicoeur, Robert Bouthillier, Vivian Labrie, Georges Arsenault, Lauraine Léger, Jean-Claude Dupont, Charlotte Cormier and Ronald Labelle. In the 1990s, Robert Richard followed in their footsteps.
The Acadians did not leave a large-scale built heritage. They are recognized, however, for certain artisanal practices and ancestral customs. In 1980, the Musée acadien (Acadian Museum) in Memramcook, founded in 1886 by Father Clément Cormier, moved into a new building on the Université de Moncton campus. The museum collection, consisting of more than 35,000 objects and photographs, is the richest assemblage of artifacts representing the tangible culture of Acadia.
The link between Acadia and its folklore has yielded a significant literary heritage: history books, legends, songs, recipes and novels. Research and field studies begun more than 50 years ago still provide material for artists and for performers with an interest in the oral tradition.
Tintamarre - On the Trail of Acadians in North America by André Gladu, National Film Board of Canada
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Directions: Choose the option for the underlined portion that best expresses the idea in standard written English and that is most consistent with the style and tone of the passage. If the original version is correct, select NO CHANGE. If there is a question provided, choose the best answer to the question.
The Origins of Coca-Cola
Coca-Cola history began in 1886 when the curiosity of an Atlanta pharmacist Dr. John S. Pemberton, led him to create a distinctive tasting soft drink that could be sold at soda fountains. He created a flavored syrup and took it to his neighborhood pharmacy, where it was mixed with carbonated water and deemed “excellent” by those whom have sampled it. Dr. Pemberton’s partner and bookkeeper, Frank M. Robinson, is credited with naming the beverage “Coca‑Cola” as well as creating the design of the trademarked, distinctive script that is still used today. The first servings of Coca‑Cola were sold for 5 cents per glass. During the first year, sales initially averaged a modest nine servings per day in Atlanta. Today, daily servings of Coca‑Cola beverages are estimated at 1.9 billion globally.
In 1888, Dr. Pemberton sold portions of his business to various parties, just two years after creating what was to become the world’s #1-selling sparkling beverage however only a few years before his death. [1] The majority of the interest was sold to Atlanta businessman, Asa G. Candler. [2] Under Mr. Candler’s leadership, distribution of Coca‑Cola expanded to soda fountains beyond Atlanta. [3] In 1894, impressed by the growing demand for Coca‑Cola and the desire to make the beverage portable, Joseph Biedenharn installed bottling machinery in the rear of his Mississippi soda fountain, becoming the first to put Coca‑Cola in bottles. [4] The three entrepreneurs purchased the bottling rights from Asa Candler for just $1. [5] Benjamin Thomas, Joseph Whitehead and John Lupton developed what became the Coca‑Cola worldwide bottling system. [6] Large scale bottling was made possible just five years later, when in 1899, three enterprising businessmen in Chattanooga, Tennessee secured exclusive rights to bottle and sell Coca‑Cola. [ ]
Among the biggest challenges for early bottlers was the imitations of the beverage by competitors coupled with a lack of packaging consistency among the 1,000 bottling plants at the time. The bottlers agreed that a distinctive beverage needed a standardized, distinctive bottle, and in 1916, the bottler’s approved the unique contour bottle. The new Coca‑Cola bottle was so distinctive it could be recognized in the dark, and it effectively set the brand apart from competition. Over the years, the Coca‑Cola bottle has been inspiration for the work of artists across the globe — a sampling of which can be viewed at the World of Coca‑Cola in Atlanta. The contoured Coca‑Cola bottle was trademarked in 1977.
The first marketing efforts in Coca‑Cola history were executed through coupons promoting free samples of the beverage. Considered an innovative tactic in 1887; couponing was then followed by newspaper advertising and the distribution of promotional items bearing the Coca‑Cola script to participating pharmacies.
[ ] Many fondly remember the 1971 Hilltop Singers performing “I’d Like to Buy the World a Coke” or the 1979 “Have a Coke and a Smile” commercial featuring a young fan giving Pittsburgh Steeler “Mean Joe Greene” a refreshing bottle of Coca‑Cola. Though these marketing campaigns began in the 1970s, Coca‑Cola commercials are still aired today.
This passage was adapted from “Coca-Cola History.”
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What was the purpose of the Kellogg-Briand Pact?
Quick Answer
The purpose of the Kellogg-Briand Pact was to basically outlaw war. The pact was signed, in August of 1928, by France, Germany and the United States. The pact is named after its two authors, Frank B. Kellogg and Aristide Briand.
Continue Reading
Full Answer
Other countries began to sign the agreement a short time later, but the pact was soon shown to be flawed by Japan in 1931. The Asian country invaded China and with economic issues, along with the lack of desire to go to war there was no attempt to enforce the sanctions set up in the pact. The pact was later tested by the Axis powers in World War II, showing that it was not going to be possible to enforce the pact.
Learn more about Modern History
Related Questions
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By comparing the legs of 330 species, German biologists determined that the sticky feather-like hairs at the end of the leg, called setae, evolved from hairy pads that originally helped the spiders wrangle food. Now, the hairs provide 32,000 contact points per leg, enabling the arachnids to walk up walls.
Other appendages also help with the hunt: two claws for grasping and bristles that detect air currents, tastes, and smells. To jump, the spider directs its hemolymph to the legs. The sudden rush causes them to extend all at once, and the spider goes flying.spiderJonas O. Wolff
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"url": "http://www.businessinsider.com/heres-a-super-close-look-at-a-jumping-spiders-leg-2013-10"
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Father and His Sons
Father and His Sons
Photo by: sumana
sumana Submitted by: sumana
The moral of this story: United we stand, divided we will fall.
10 minutes
36 - 60 months
Group size
1 - 8 tots
An old farmer was worried about his four quarrelsome sons. One day he became sick. He called his sons and asked them to bring him some sticks. The farmer gave each of his sons one stick. He asked them to break the stick, which they were able to do very easily. He then asked the elder son to bundle all the sticks and then try break them. He could not do so. The father then said to his sons, "See my sons, if you are separate, you can break easily. As long as you are tied together nobody will harm you." The boys took fathers advice and stopped quarrelling. From thereafter they lived in peace and made their father proud.
Discussion Questions
1. Why was the Old Farmer worried about his sons?
2. How did the old farmer get the sons to stop quarrelling?
3. Why do you think it is important for families to stick together?
Developmental skills
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The Rusty Blackbird is not a legally protected species nationally, despite its numbers still being in decline.
Photo © Steve Byland \
Imagine you’ve just opened your eyes, and you’re in the hospital. You’ve had surgery after a catastrophic heart attack. You’re lucky to be alive.
A nurse comes to check on you. “Oh, you’re awake,” he says, then promptly puts you in a wheelchair, pushes you beyond the sliding doors, and leaves you. Your care – and your health coverage – is over. You’re on your own.
This sort of treatment is unthinkable for a human, but this what it is like for endangered species in today’s world – even ones that are legally protected. As soon as the health of a species has stabilized, starts to show signs of improvement, or even if deterioration has merely slowed, they usually lose this protection. As you might expect, though, a relapse back into critical condition isn’t difficult. As it turns out, this entire problem hinges on one seemingly simple word: recovery.
The word recovery denotes the process of improving health with an end goal of reaching a recovered state. However, when it comes to conservation, governments and academics alike conflate the process of recovery with the state of being recovered.
This can lead to the bizarre situation of having a species still in decline actually being assessed as not at risk and losing its protected status. A particularly dire example is the Rusty Blackbird. When its status was assessed in Canada, it was assigned ‘Special Concern.’ Species of Special Concern don’t receive legal protection the way that Threatened or Endangered species. The rationale for this was that though declines were ongoing, they were slower than rates of decline in the past. However, the overall loss of Rusty Blackbirds is somewhere between 90 and 99%. That’s still millions of birds dead – they just happen to be dying more slowly. The situation is much like having an active cancer, but stopping treatment as soon as growth has slowed, and resuming once it becomes aggressive again. This might qualify as “in recovery,” but it certainly isn’t a recovered state.
With no common understanding of either recovery or recovered, there is also no framework to guide the recovery of species at risk. There is no universal definition of what recovery looks like and no way to compare recovery plans. Quite simply, there is no way to know what conservation methods lead to species reaching a recovered state. Species at risk legislation also often omits any discussion of recovery at all. The outcome: ad-hoc global attempts at recovery that have little success, leaving vulnerable species in trouble despite our best efforts to help them.
Conservation organizations and policies were set up to prevent species extinction, but their approach isn’t complex enough. Conservation isn’t just about preserving single species. It is about maintaining healthy populations and healthy ecosystems that can fill ecological niches and contribute ecosystem services such as clean water, pest control, and waste management, to name but a few. We need healthy populations functioning in their ecosystems, not a handful of organisms clinging to life support.
The present situation is not only failing to protect species that are still in trouble, but is wasting the potential of the millions of dollars that go into much-needed conservation work each year. That’s why my colleagues and I have proposed a new framework to assess species and make sure they are actually in a sustainable healthy state before they become unprotected.
A new, generalized framework for assessing species recovery.
Right now, protection often ends at what would be stage two of this framework.
This new framework has five stages: diagnosis, treatment, stabilization, rehabilitation and recovered. What constitutes a recovered state for a particular species needs to be defined during diagnosis, based on the best available science. Like a patient in an ER, species at risk need to be monitored throughout the recovery process, until they are finally assessed as reaching a recovered state. Just as we wouldn’t send a patient who had open heart surgery home as as they open their eyes, we can no longer simply perform triage on a species and send them on their merry way once they are no longer at imminent risk of extinction. As with any patient, we need to follow up: measure, monitor and quantify their recovery until we are sure they are safe. We cannot take their recovery for granted.
Not only do we owe this much to them, but we owe it to ourselves. By seeing endangered species all the way through on their road to recovery (and by acting before populations reach an endangered state), our conservation dollars are spent more effectively. And we have a better chance of maintaining healthy ecosystems, on which the survival of our own species is dependent.
Alana Westwood is a Ph.D. candidate doing endangered species research in Nova Scotia. She was a member of the 2012 Canadian Youth Delegation to the UN climate change conference in Qatar, and you can follow her goings-on at
Comments may be considered for publication in the magazine.
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22 June 1991
Science: DNA prints show how lions keep it in the family
Using DNA fingerprinting, biologists in the US have gained new insights
into the social behaviour of lions. Prides of lions are complex societies
in which cooperation plays an important part, especially in hunting, defence
and care of cubs. Much of this cooperation is based on kinship: lionesses,
for example, work together because they are close relatives.
Craig Packer of the University of Minnesota and his colleagues have
discovered new information about genetic relationships within the pride
and elegantly reveal how kinship affects cooperation (Nature, vol 351, p
DNA fingerprinting is ideal for analysing the make-up of groups of animals
such as prides of lions. Each fingerprint takes the form of a unique pattern
of dark bands. The bands are inherited in a straightforward fashion and
so close relatives have more bands in common than distant relatives, who
in turn bear more resemblance to one another than non-relatives.
The researchers took DNA fingerprints from more than 200 lions in the
Serengeti National Park and Ngorongoro Crater, Tanzania. These lions have
been the focus of research for several decades. So by analysing the DNA
fingerprints of animals whose genealogy was already known the team derived
rules of thumb for converting data from fingerprints into estimates of genetic
relatedness. Among the Serengeti lions, for example, a pair of siblings
tend to have about 80 per cent of their bands in common, while a pair of
unrelated individuals share about half of their bands.
Packer and his colleagues confirmed that the lionesses in a pride are
close relatives and that they are usually unrelated to the males with which
they consort. This is to be expected, because males acquire prides by force,
ejecting resident males, killing or driving out their cubs and then siring
a new generation. To succeed in this male lions must enter into cooperative
alliances with other males. These coalitions are often forged between close
relatives – half brothers, say – but they are sometimes made up of non-relatives.
But how far does this cooperation go? In a large coalition, not all
males get a chance to breed, so some are reduced to the status of helpers.
Packer’s team found that these large inequitable coalitions are invariably
made up of close relatives. This helps to explain the helpers’ celibacy.
They co operate with their pride-mates because in doing so they further
the interests of their own kind. Lions in large coalitions sire more cubs
per head than those in small coalitions, even though some of them have no
access to females.
Lions that throw in their lot with non-relatives, on the other hand,
cannot afford to make self-sacrifices on this scale. They limit themselves
to small alliances (duos and trios) that give each more chance to sire cubs.
Enlightened self interest, not kinship, underpins their cooperative behaviour,
but such a mechanism can only work in small groups. In forming its alliances,
the lion displays a powerful grasp of politics.
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Question on motion of a ship
1. Jul 6, 2009 #1
A ship which is at rest,is connected to land by a chain.The ship is powered by 2 propellers.When the ship is moving ,the 2 propellers push the water backward with velocity 20ms-1,relative to the earth.density(dw)of seawater is 1000kgm-3.Total mass of the ship(M)is 2*107kg
(1)The effective area swept by the blades of a propeller is 12m2,calculate the mass of water pushed in 1 second.
(2) Calculate the force exerted on the 2 propellers by water
(3) what is the initial acceleration (a)of the ship if the chain is released?
(4) goods of weight 4*106kg are unloaded from the ship at a harbor.Cross sectional area of the ship base is 1000m2.Assuming the hull of the ship is vertical,cal.the height raised by the unloading
(5) As the ship is raised,there's a danger of it falling to a side.how much volume of water must be taken in to submerge it to the previous level?
(6) The ship is loaded back with new goods & the water taken in is removed,before it starts sailing.Height submerged in the water is 5m.Due to a blast,a small hole is formed at the base.find the initial speed of water entering the ship?
(7) water enters the ship at the rate of 10m3s-1,and the height of the ship is 8m.calculate the time taken for the ship to submerge fully
(8) once the ship is fully submerged it reaches the sea bottom.If the average density of the material of the ship is 2500kgm-3.Cal the min,force requied to bring the ship back to the surface
2. Relevant equations
3. The attempt at a solution
I'm sorry the question's so long.
It seems like a very easy question and I managed to do it upto (6).
(1) Volume of water pushed out/s = Au
massof water/s=dw*V
(2) [tex]\stackrel{\rightarrow}{F}[/tex] = ma
480*1000*20= -9.6*106N
(3) [tex]\stackrel{\rightarrow}{F}[/tex] = ma
-9.6*106/2*107 = a
= -0.48ms-2
(4) P = F/A
hdg = 4*107/1000
(5) V= A*8
(6) P1 at the bottom of vessel = pi + 5dg
P2=pi=atmosphric pressure
(P1-P2)A = m(v-u)/t
5*104*103= m(v-u)/t
It's here that i'm stuck,i don't know how to proceed without m/t,I'd like to think the m/t here is the same as what i got in (1),but i don't think that's possible.
Hope someone can help.
2. jcsd
3. Jul 6, 2009 #2
User Avatar
Homework Helper
I'm wondering why the answer in 4 seems different from the answer in 5? If the cargo displaced some amount of water won't that same volume be needed to reload the boat back to the same level?
In 6) don't they want to know the speed of the water? Won't it be related to the kinetic energy in the water? Won't the potential energy released at 5 meters become kinetic energy as in
p*g*h = 1/2*p*v2
7 is just a how long to fill isn't it? It is already 5 m submerged with only 3 meters to go before swimming with the fishes.
In 8 won't you need to add just enough buoyancy to bring it up? The density is 2500 but it already displaces 1000, so it will need additional displacement of water to get it to the surface?
4. Jul 6, 2009 #3
Yes,I think I've made a mistake here,the answer for(5) should have been ,
Area of base*4=1000*4=4000m3 , right?
which would mean,
2gh= v2
=[tex]\sqrt{100}[/tex] = 10ms-1 ?
Therefore t = (3*1000)/10
= 300s ?
All of the above I understand,thanks to your very helpful hints,sir.
Now,it is this part that I'm having trouble understanding,
What is this 1000 you're referring to,sir?
Since the ship needs to sink by 3m to get fully submerged,would it be wrong to just take,
= (3*1000)*1000*10
=3*107N ?
5. Jul 6, 2009 #4
User Avatar
Homework Helper
The 1000 kg/m3 is the density of water right?
And if something submerged has a density of 2500 kg/m3 doesn't that mean it already displaces 1000 of the 2500 kg/m3? Doesn't that mean that you only need to supply an additional 1500 kg/m3 to make it buoyancy neutral in water? That's what is required to make it be able to come to the surface. To get it above the surface you will need more of course.
The only thing you are missing is what is the volume of the 2500 kg/m3. But that it looks to me like you can figure from the original mass of the boat and the additional mass of the cargo added. Then that volume times 1500 kg/m3 should be all that's needed to bring it off the bottom to just at the surface.
6. Jul 6, 2009 #5
I'm still finding it difficult to understand this.
so interms of density,we have to supply the additional density (for any submerged object),to balance its density?
Does this include the density of the load as well?
I'm just so confused.
7. Jul 7, 2009 #6
User Avatar
Homework Helper
The statement says the average, so that would be the cargo too supposedly.
As to density ... you are not going to supply density, you need to supply volume ...
Total mass / average density = Volume of submerged ship and cargo.
That volume times the difference in average density and water ... 2500 kg/m3 - 1000 kg/m3 or 1500 kg/m3 is the buoyant force you need.
8. Jul 7, 2009 #7
To find the total mass of the ship+ new cargo,
Assuming all the cargo was removed in part(4),
to find the mass of the ship only,
=20*106 - 4*106
To find the mass(x) of the new cargo added in part(6),
P=F/A = xg/1000
=xg/1000 = h*1000*g
=x= 5*106kg
so total mass= 5*106 + 16*106kg
Total mass / average density = Volume of submerged ship and cargo
21*10^6/2500 = V
V*1500 *10 = force needed
(21*10^6/2500)*15000 = F
Is this correct?
Though I'm still a bit unclear about the density part.
9. Jul 7, 2009 #8
User Avatar
Homework Helper
It may be. But my reading of the problem suggests that the mass of the ship alone may be 2*107 kg. So either you need to consider that the ship + cargo is 25*106 or 21*106 as you found. I think the problem is ambiguous on this point.
The important thing is you grasp the concept that buoyant force is given by the amount of water displaced, and that for a submerged object it already has a buoyant force on it given by the volume of water it displaces. Meaning that the weight (downward force) of a submerged object is really only the weight given by the difference in density between it and water multiplied by its volume.
10. Jul 7, 2009 #9
I'm sorry,I still find it difficult to understand this.
Are we talking about the Archimedes' principle,here?
i.e.,if an object floats totally or partially immeresed in a fluid at rest,then the weight of the body is equal to the weight of the fluid displaced by the body?(this is what you mean here,ryt?)
so the upthrust or bouyant force acting on this body = volume of the body*density of fluid immersed in*g?
are you referring to the apparent weight of the body in the liquid,here?
& do we always have to find the difference in densities to find the upthrust of an object immersed in a fluid?
I've never substracted the densities before to find the upthrust acting on a body,so this is very new to me.
Do we always have to find the difference or is it only under certain conditons?
I'm just so thoroughly confused and I would really like to understand.
thank you
11. Jul 7, 2009 #10
User Avatar
Homework Helper
Whatever volume a submerged object occupies times the density of water is the buoyant force acting on it. If it is heavier than water, then the "apparent" weight, say if you put a scale under the water, would be lessened by that amount.
Mass = volume * density
Weight = mass * gravity
Weight under water = mass * gravity - buoyant force
Buoyant force = density water * volume * gravity
Weight under water = density object * volume * gravity - density water * volume * gravity
Weight under water = volume * gravity * (density of object - density water)
Well you won't find "upthrust" that way, subtracting densities is used to determine the excess mass that needs to be supported for an object submerged. The "up" force is the buoyant force, which is how much water is displaced.
Usually problems involving buoyancy are about things floating on the water. But when an object doesn't displace enough water to float the force is still there at least to the extent that it is still displacing water and off setting some of it's mass (weight) in the downward direction.
Last edited: Jul 7, 2009
12. Jul 8, 2009 #11
Wow.this is perfect.
this is just the explanation i needed,and i feel like i finally understand it all,but i guess the only way to really findout is to attempt more questions,so if i have any problem,i will post.
Thank you
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fold (n.1)
"pen or enclosure for sheep or other domestic animals," Old English falæd, falud "stall, stable, cattle-pen," a general Germanic word (cognates: East Frisian folt "enclosure, dunghill," Dutch vaalt "dunghill," Danish fold "pen for sheep"), of uncertain origin. Figurative use by mid-14c.
fold (n.2)
"a bend or ply in anything," mid-13c., from fold (v.). Compare similarly formed Middle Dutch voude, Dutch vouw, Old High German falt, German Falte, Old Norse faldr.
fold (v.)
Old English faldan (Mercian), fealdan (West Saxon), transitive, "to bend (cloth) back over itself, wrap up, furl," class VII strong verb (past tense feold, past participle fealden), from Proto-Germanic *falthan, *faldan (source also of Middle Dutch vouden, Dutch vouwen, Old Norse falda, Middle Low German volden, Old High German faldan, German falten, Gothic falþan), from PIE *pol-to-, suffixed form of root *pel- (2) "to fold."
Of the arms, from late Old English. Intransitive sense "become doubled upon itself" is from c. 1300 (of the body); earlier "give way, fail" (mid-13c.). Sense of "to yield to pressure" is from late 14c. The weak conjugation developed from 15c. Related: Folded; folding.
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A judicial executioner is a person who carries out a death sentence ordered by the state or additional legal authority, which was known in feudal terminology as high justice. Note that the role of an executioner shouldn't be confused with that of an executor, a person who's responsible for executing (meaning "following through on") an assigned task or duty.
Scope and job
The executioner was usually presented with a warrant authorising or ordering him to execute the sentence. The warrant protects the executioner from the charge of murder. Common terms for executioners derived from forms of capital punishment—though they often additionally performed additional physical punishments—include hangman (hanging) and headsman (beheading). In the military, the role of executioner was performed by a soldier, such as the provost. A common stereotype of an executioner is a hooded medieval or absolutist executioner.
Many executioners were professional specialists who travelled a circuit or region performing their duty, because executions would rarely be quite numerous. Within this region, a resident executioner would additionally administer non-lethal physical punishments, or apply torture.
The term is extended to administrators of a severe physical punishment that isn't prescribed to kill, but which might result in death.
Executions in France (using the guillotine after the French Revolution) persisted until 1977, and the French Republic had an official executioner; the last one, Marcel Chevalier, served until the formal abolition of capital punishment in 1981.
Executioners in society
The lack of social shunning for executioners in places like North America might be attributed to the infrequency of executions in modern times and the ease in which prison or judicial officials are able to conceal their daily job duties. This provides anonymity that wasn't possible when executions were carried out in view of the general public.
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Native American Writer and Activist Susette La Flesche
Smithsonian Institution/ National Anthropological Archives // Public Domain
In 1879, one of the most popular speakers on the East Coast of the United States was a young Native American woman who would eventually help earn several important “firsts” for herself and her people.
Susette La Flesche was born in 1854 in Bellevue, Nebraska and given the name Inshata-Theumba, or Bright Eyes. Her father, Joseph La Flesche—also known as E-sta-mah-za, or Iron Eye—was the last traditionally recognized chief of the Omaha tribe, and the year Susette was born, he and other tribal leaders signed a treaty with the federal government giving up traditional Omaha lands and moving their people to a small reservation in what is now northeastern Nebraska, near a related tribe called the Ponca.
Like many Native American children of that era, Susette and her siblings attended a mission school, where she learned English as well as domestic skills such as sewing and cooking (several of the La Flesche siblings would also go on to illustrious careers, including Susette's sister Susan La Flesche Picotte, who became the first Native American woman to earn a medical degree). Susette attended college at New Jersey’s Elizabeth Institute for Young Ladies, where she studied art and excelled at writing, and after she graduated, she decided to return to the Omaha reservation to teach. In the late 1870s, however, her life took a turn.
Around 1875, after decades of conflict with both the U.S. government and Sioux tribes that had been relocated to their land, the Ponca nation considered an offer to move to Indian Territory in Oklahoma, about 500 miles away. But when Ponca leaders visited potential settlement sites in early 1877, they rejected all of them as uninhabitable, with "stony and broken land" and poor, dispirited residents [PDF]. The government agents who were trying to find a resettlement point were unable to get further instructions from Washington and refused to transport the leaders back home, so the Ponca leaders walked back to Nebraska (except for two elders who were too frail to make the trip), arriving footsore and hungry in March 1877.
Although the specifics are debated, many historians think what happened next was due to a poorly translated deal that the Poncas thought would allow them to move to Omaha land but actually committed them to move to Indian Territory. The majority of the tribe was eventually made to walk to Baxter Springs, Kansas in the spring of 1877, an echo of the Cherokee Trail of Tears of the 1830s and the Long Walk of the Navajo in the 1860s, and with similarly devastating results. As many as one-third of the Ponca nation died of disease and starvation during the march and their first year in Indian Territory, including the son of Chief Standing Bear. After a miserable winter, the remainder of the tribe walked to a new reservation on the Arkansas River, in what is now Oklahoma. In January 1879, Standing Bear and a small party of Ponca set out for Nebraska again so that Standing Bear could bury the bones of his son on ancestral land. Once back in Nebraska, Joseph La Flesche and his daughter helped shelter them in the Omaha village. But after a confrontation with the U.S. government, Standing Bear and his companions were arrested and tried in 1879 in a federal district court in Omaha.
La Flesche was fluent in English and French as well as the Omaha and Ponca languages. Though she was incredibly shy, she became translator for Standing Bear, testifying during the trial in 1879 and writing for newspapers about the plight of Nebraska’s native peoples. At last, Judge Elmer Dundy issued a narrow but consequential ruling in favor of the Ponca: “An Indian is a person within the meaning of the law, and there is no law giving the Army authority to forcibly remove Indians from their lands.” Standing Bear v. Crook marked the first time Native Americans were recognized as people, entitled to protections under U.S. law.
As a result of the trial, the Ponca were allowed to return to a portion of their land in Nebraska. La Flesche, however, was only just getting started. With Standing Bear, her half-brother Francis, and an Omaha newspaperman named Thomas Tibbles—a lifelong reformer who had been instrumental in raising awareness of the Ponca's plight and whom she later married—La Flesche went on a speaking tour back East. She wore a deerskin dress and presented herself using her translated tribal name, Bright Eyes, speaking out about conditions on reservations and calling for overhauls of federal Indian policies. By 1887, she was touring England and Scotland during Queen Victoria’s Jubilee Year, lobbying for the rights and fair treatment of Aboriginal peoples in Canada. “Bright Eyes” had become an international sensation.
La Flesche also testified before Congress, met with President Rutherford B. Hayes and the first lady at the White House, and gained the admiration of poet Henry Wadsworth Longfellow. She embarked on a distinguished writing and journalism career, one that would take her to the Pine Ridge Indian Reservation in in southwestern South Dakota to report on both the Ghost Dance movement and the massacre at Wounded Knee. She also wrote about Native American life for children’s magazines, and illustrated at least one book. For her efforts, she has been called the first published Native American writer and artist. She was also deeply involved in the Populist Party (a group that championed agrarian interests and industrial workers against bank and railroad titans), writing for papers like the American Nonconformist and the Lincoln Independent.
La Flesche died on May 26, 1903, at the age of 49. She was inducted into the Nebraska Hall of Fame in 1983. “Peaceful revolutions are slow but sure,” she once wrote. “It takes time to leaven a great unwieldy mass like this nation with the leavening ideas of justice and liberty, but the evolution is all the more certain in its results because it is so slow.”
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The Indo-European language family includes most of the languages of Europe as well as many languages in Asia. There is a long research tradition that has shown, though careful historical comparison, that languages spanning a huge linguistic and geographical range, from French to Greek to Russian to Hindi to Persian, are all related to each other and sprung from a common source, Proto-Indo-European. One of the techniques for studying the relationship of the different languages to each other is to look at the similarities between individual words and work out the sound changes that led from one language to the next.
This diagram, submitted to Reddit by user IronChestplate1, shows the word for two in various Indo-European languages. (The “proto” versions, marked with an asterisk, are hypothesized forms, built by working backward from historical evidence.) The languages cluster around certain common features, but the words are all strikingly similar, especially when you consider the words for two in languages outside the Indo-European family: iki (Turkish), èjì (Yoruba), ni (Japanese), kaksi (Finnish), etc. There are many possible forms two could take, but in this particular group of languages it is extremely limited. What are the chances of that happening by accident? Once you see it laid out like this, it doesn’t take much to put *dwóh and *dwóh together.
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Beyond Plumbing: 19 Other Jobs on Mario's Resume
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Nintendo made news this week by subtly announcing that Mario is no longer a plumber. In fact, they're really downplaying his whole plumbing career. On the character's Japanese-language bio, the company says, "He also seems to have worked as a plumber a long time ago."
But Mario has always had plenty of jobs on the side. Here's a look at his resume:
More from mental floss studios
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The big bone count
femurs and other bones in a plastic bag
Several weeks ago, work began to determine a preliminary count of how many individuals were recovered from the Arch Street site in the early stages of discovery. The remains of these individuals are stored in more than 50 boxes, which are housed at Rutgers University, Camden. A portion of the boxes are thought to contain single individuals, corresponding to single burials. Many boxes, however, contain bones that obviously originated from more than one person, such as two skulls, two sacrum, or two right-sided femurs. The boxes also contain burial goods, such as ceramics and remnants of footwear, and an assortment of animal bones. Based on early observations, it was clear that the femur was the most well-preserved bone from the Arch Street burials, and therefore a quick, preliminary tally of burials was performed by examining the femurs from these boxes.
To determine a Minimum Number of Individuals (MNI), femurs from each box were examined and inventoried. MNI refers to the fewest possible number of people or animals in a skeletal assemblage. For example, let's say there are ten different bones in a box. Six of those bones are right femurs. The MNI is six because humans only have one right femur per person. The other four bones could belong to one of those six people, or several, or could be from different people altogether. Those ten bones could be 10 different people, but the six femurs say that at the very least, there are definitely six people represented.
The preliminary total MNI for the Arch Street boxes was determined to be 83, including at least four children/infants. The highest MNI per box was seven, while most boxes contained between one and three individuals. This count does not include the contents of the “original” box of bones currently housed at The College of New Jersey, nor the 78 coffins excavated from the site between March 7 - 13.
Future robust analyses of the remains recovered from the Arch Street site, involving the inventory of all elements and even measurements, will no doubt increase the minimum number of individuals to well over 100, and likely beyond 200.
For questions regarding this count or our preliminary analyses, please contact Allison Grunwald.
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GCSE English coursework: Short Gothic Tales
Extracts from this document...
GCSE English coursework In these two short stories both authors write gothic tale stories. Both authors use gothic tale features e.g they use darkness, isolation and use of senses. Both authors' u similar methods to create tension e.g. they both use repetition and short sentences. They both use their senses e.g. in the monkeys paw they use their sense of hearing and feeling, for example they hear the door knocking and use a lot of sight through Mr.White cant see where the monkeys paw is and he use his sense of feeling to try and find it on the floor. In the signalman they use a lot of feeling, for example "It was made of a clammy stone, that became oozier and wetter as I went down." In "The monkeys paw" W.W.Jacobs creates tension several times e.g. when the sergeant-major says "Hold it up in your right hand and wish aloud" then says "But I warn you of the consequences," and then Mr.White wishes straight after. He makes a lot of tension when the man is walking back and forth outside of Mr.White' gate, and then when he finally comes to the door he starts to use short sentences and a lot of question asking e.g. "Is anything the matter? She asked breathlessly. Has anything happened to Herbert? What is it? What is it?" He creates a lot of tension at the end of the story when they wish Herbert to live again, there was several knock and as his wife goes to open the door he just gets to wish before his wife opens the door. ...read more.
Jacobs uses sounds and noises effectively several times in the story e.g. the banging of the gate and the heavy footsteps of the sergeant walking to the front door. There was door banging upstairs mysteriously. There was sounds of weeping from outside in the nights. They could hear the stairs creak and a squeaky mouse scurried nosily through the wall shows how quiet they where. The weather is used effectively several times in the story e.g. towards the end when Mrs.White opens to the door hoping to see Herbert on the other side but when she opens it and "Cold wind rushed up the staircase," which shows that nothing was there and it's just a lonely atmosphere outside. Darkness adds tension in several parts of the story. One example of this is when Mr.White had a lit match and then, when the match went out, then when there was knocking at the door, the darkness created dark atmosphere because Mr.White couldn't fin the paw and it was tense if he was or wasn't going to find and wished to undo his last wish before his wife opened the door. In "The signalman" Charles Dickens creates tension by using a variety of techniques e.g. The story opens with a hook. It makes you want to know why the narrator was so interested about the signalman and why was the man looking down at the line instead of where the voice came from, it says to the reader that something has happened to this signalman and it has frightened him. ...read more.
The author makes use of sounds to add tension. One example of this is when the signalman hears screams and cries when he is running after the thing that he is seeing. In my opinion 'The Monkeys Paw' by W.W.Jacobs is the most effective. There are several examples of The reader is drawn into this story because it has a hook, the opening paragraph tells you what kind of settings there is, which were isolated settings, which gives you a thought that it might be a horror or a ghost story. The reader is on the edge of his seat at several points in the story e.g. My favourite part and the best part of the story was when Herbert was joking with 'The Monkeys Paw' when he said "Well I don't see the money, and I never shall," then the next day he got caught in the machinery and died and the family received two hundred pounds in Herbert's will as compensation of the company. The conclusion is very effective because it makes a very tense atmosphere just before it ends and it gives you the feeling what would've happened if Mr.White didn't undo his second wish. It makes you want to know more about the story because you want to know will Mrs.White know that her husband used the third wish to demolish the second wish, and what will Mrs.White react to this. Also it makes you want to know if Mrs.White doesn't find out what her husband wished for will she be waiting and waiting for her son Herbert to relive. ...read more.
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See related essaysSee related essays
Related GCSE The Signalman essays
1. Literature G.C.S.E Prose Critique
However, this beginning is more puzzling because 'sunshine' and 'white roses' have positive connotations and are usually associated with pleasure. The 'I' before the name Harry is clever as it creates extra tension and suspense before the name is revealed.
"I kept quite still and said nothing. For a whole hour, I did not move a muscle" This quote creates Suspense, because the reader anticipates what is going to happen next. Also this quote is slowly building up to the main climax of the story (the murder).
After a cryptic silence, the veiled woman leads the doctor to a room upstairs. The room has obviously been neglected, just like the rest of the 'damp' house. A dim light is emitted through a curtain' and the objects in the room prove 'indistinct' because of this.
2. Compare and contrast three 19th Century gothic short stories commenting upon the authors' use ...
The setting is unwelcoming to the reader and also allows the writer to build up the tension. For the most part, the story takes place in the signalman's box, which is positioned along side the track. On one side of this box, is a 'black tunnel,' suggesting images of hell
1. Analysing 4 Short Horror Story Openings.
He then goes on to say that "whenever it fell upon me, my blood ran cold." The eye obviously made him uneasy in some way because the phrase "my blood ran cold" we usually associate with terror or horror. When he is preparing for the murder, why does it take
2. How do Dickens and W.W. Jacobs create a strong sense of dramatic tension in ...
These comments give a feeling of hopelessness, and we know that events are heading towards an inescapable conclusion. The same feeling is present in 'The Monkey's Paw' because once the father has made his wish for the money, we know that he will not simply get his wish, but we
1. Comparing the Signal man and monkey's paw (part 1)
"The monkey's paw" is a good example their supernatural interest. "Monkey's paw? Said Mrs White curiously. Well it's a bit of what you call magic perhaps. Said the Sergeant major.". This explains to us the curiosity of the Victorian population over the supernatural. Another example is in "The signal man".
2. Which of the Two Horror Stories: &quot;The Monkey's Paw&quot; or &quot;The Signalman&quot; Do you ...
Throughout the narrative the mood of the setting varies. W.W.Jacobs does this to create tension and then constantly release it, building up a series of anti-climaxes which have us constantly engrossed in the story.
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Amadeo Avagadro
Amedeo Avogadro was born on June 9, 1776 in Turin, Italy. As he persued his career in chemistry and physics he based most of his work on the findings of Joseph Gay-Lussac in 1809. Gay-Lussac had discovered that all the gases when subjected to an equal rise in temperature, expand by the same amount. He also made it clear that the gas particles need not be individual atoms but had made a distinction between the atoms of a substance and its molecules. Avogadro therefore derived his hypothesis known as Avogadro's Law. His law states that a given temperature, equal volumes of gases contain the same number of molecules equal to 6.02252E23.
Avagadro no recognition for his work during his lifetime. This was because of a few reasons. One was because he did not back up his hypothesis with enough experimentation to get the respect of the scientific community. He also did not possess a good reputation for experimentation, and he was fairly isolated from the scientific mainstream. Avagadro's work was not recognized for 50 years after he had made his hypothesis.
Two years after his death, his colleague showed how the use of Avogadro's number could solve many of the problems in chemistry. This time Avogadro's paper was looked at more carefully over a wider and more distinguished group of scientists, thus his work was finally recognized. From his hypothesis, using Avogadro's number, scientists arrived at the mole (6.02 x 10²³). Avogadro's work helped other scientists to solve more problems and develop more theories.
Avagadro died on July 9, 1856 in Turin, Italy.
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Introduction to structural integrity
Introduction to structural integrity
Free course
Introduction to structural integrity
2.6.3 Boiler explosions
Stress corrosion cracks can also build up in other structures. These were a particular problem in locomotive boilers in the early days of the railways in Britain. All such boilers were made from wrought-iron sheet, riveted together to form a cylinder. In the earliest engines, the boilers were constructed using a single line of rivets, thus forming two corners, one inside and the other outside (Figure 25). Initially they apparently performed well, but a number of catastrophic explosions were experienced through the 1840s.
Figure 25
Figure 25 Riveted joint between two wrought-iron sheets in boiler construction
Some of the earliest explosions were caused by failures of the safety valves fitted to the boilers. For example, some of the first safety valves were simply a stopcock weighed down by a steelyard. The weight and its distance along the arm controlled the pressure at which steam would activate the cock, and so blow off harmlessly. It was tempting for engine drivers to increase boiler pressure by adjusting to the highest possible pressure – and if that didn't give enough driving power to the wheels, they would wedge the valve down further. Such manipulation of a safety device was asking for trouble. Another problem that also caused some explosions was that if the water level dropped too far, the structure would overheat and fail.
Many such boiler explosions were investigated by the Railway Inspectors appointed by the Board of Trade (one of the predecessors of the Department of Trade and Industry). They found that they could not always explain why the explosions had occurred, having excluded both human negligence in the use of the safety valves and the water level. When the inspectors examined the failed remains in some detail, they found a pattern revealing that failure almost always occurred from the horizontal line of rivets in the boiler, and there appeared to be a deep groove running alongside the joint that was filled with rust.
Explain why failure tended to occur along the longitudinal axis of the boiler.
Why would a riveted joint represent a line of weakness? How could such a joint be strengthened?
There are two stress components in the wall of a cylindrical boiler, the hoop stress and the longitudinal stress. The hoop stress is twice the longitudinal stress and is given by the equation:
where p is the internal pressure, r the radius of the cylinder and t the wall thickness.The hoop stress acts such that the cylinder will fail by a lengthways crack (rather than a radial crack).
A riveted joint will always be weaker than continuous material, simply because it is a break in the uniformity of the wall. The rivet holes themselves are stress concentrators, and a line of rivets is a line of such defects, so the line of rivets is the weakest part of the structure.
The problem could be tackled by replacing the lap joint with a butt joint (Figure 26), reinforced by extra layers of riveted metal.
Figure 26
Figure 26 Section of an eye-bar joint in the Silver Bridge
The root cause of the problem lay in corrosive attack of the wall to one side of the joint, owing to the nature of the joint itself. The wall on either side would, when the pressure was being raised first thing in the morning, experience higher stress than the double wall thickness at the joint itself, owing to the existence of a corner where the plates met acting as a stress raiser. Corrosion of the iron by the boiler water tended to start here in the form of a slowly growing crack, a process repeated every morning the locomotive was worked. The cycling of hoop stress caused whenever steam was raised and the boiler pressurised could also have given rise to fatigue cracking, although the phenomenon was not recognised as such at the time.
The purity of the boiler water would be important in such a case, because if any dissolved salts were present they would increase its electrical conductivity and hence the likelihood of corrosion cells being set up near the joint.
Such ‘groove cracking’ was a design fault, which could be corrected only by developing a double-riveted butt joint (as shown in the answer to SAQ 2) in place of the lap joint, rigorous inspection and maintenance of locomotives and, ultimately, use of stronger steel in place of the wrought iron.
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Gladiators and Martyrs
Icons in the Arena
By Susan M. (Elli) Elliott
From The Fourth R
Volume 29, Issue 5
September – October 2016
Download the PDF version
How did prisoners who were publicly executed in horrifying and degrading ways become icons of Christian heroism, “The Martyrs” celebrated in song and story? While Christian culture now takes the martyrs’ heroic status for granted, the process by which they were transformed from objects of derision to icons of Christian heroism remains a paradox. To understand this paradox, we need to understand how another despised figure in the Roman arena became an emblem of Roman heroism: the gladiator. The martyrs became icons for Christian identity in a Christian vision of the Empire much as the gladiators functioned as icons for Roman identity in the Roman Empire. To understand how this happened, we will first consider the Roman arena, then the gladiators, and finally the martyrs as gladiators and icons of a Christian empire.
The Roman Arena, Spectacles, and Imperial Power
The Roman amphitheater was the stage on which the gladiatorial games projected Roman imperial power and Roman identity (Romanitas). To understand how accounts of Christian martyrs associate them with gladiators, we begin with the importance of the arena in Roman imperial culture.
The Arena: Projecting Imperial Power
As Rome’s power extended geographically, the amphitheater became the most prominent structure in Roman cities, the visual presence of the Empire across its vast territory. The sheer size of these structures projected imperial power. The Flavian amphitheater (the Colosseum) at Rome was the Empire’s largest building, seating 50,000 to 80,000 people. Here the emperor was seated in a special “ringside” box, a place reserved at other locations for the sponsor (Latin: editor) of the event. Beginning in the Augustan era (27 bce to 14 ce), each social class was assigned a specific seating area in the amphitheaters. This arrangement projected imperial power relations in an increasingly defined social hierarchy. Yet, at the same time, the stratified Roman audience was unified by a wall that separated it from nonRomans defeated on the arena’s sand.
The amphitheaters were constructed with a sophisticated infrastructure to stage a distinctly Roman form of spectacle, a spectacle of violent death. Audiences saw the destruction of exotic wild beasts captured at military frontiers and of elephants taken from opposing forces. They viewed mock sea battles featuring real water and real death. They watched the display and execution of “barbarian” military opponents and of criminals and saw gladiators demonstrate their combat skills by fighting to the death. In the amphitheater, the Empire re-enacted its victories by displaying its military might in massive bloodshed.
The Audience: Negotiating and Constructing Power
We tend to equate “Roman imperial power” with the power of the emperor, but imperial power also included the crowd in the arena. At Rome, where the emperor was expected to be present for spectacles in the arena, and in the provinces, where local leaders acted on his behalf, the arena was a location for a sometimes tricky negotiation between the power of the crowd and the power of the emperor. The power on display was not only that of the emperor but also the power of the Roman (and Romanized) people, and these two powers were not always in concord. Yet the arena projected the imperial power that included both the emperor and the Roman people, and it created social cohesion in a location where Romans participated in imperial power.
The influence of republican political institutions was waning in this period, and political jockeying moved increasingly to the arena where the crowd and the emperor or his representative were physically present. The very push and pull of political interests constituted part of the spectacle. The emperor played to the crowd, and sectors of the crowd played to him and to each other. Members of the crowd were not simply passive observers there to be entertained; they were also active participants.
One way the crowd projected its power was in unified chanting, called “acclamation.” Acclamations had long been used in cults and formed part of the script in ritual settings across the Greco-Roman era. At trials, the crowd’s acclamations could advocate a sentence (“X to the lions!”) or mercy (eleison/miserere). Some of the unified chanting was spread by claques, “rent-a-voice” groups hired to applaud and chant favorable slogans for a fee. Various private associations (collegia) would provide such vocal support for their patrons. On a few occasions, the crowd even chanted protests against imperial decisions. To imagine the arena, then, we need not only to see the crowds that filled the buildings (now in ruins) but to hear their roar and their chants as well. In their unified roar, they felt their power as Romans.
The spectacles themselves were also a means of social cohesion, a bonding experience in the spectacle of death. They not only projected imperial power but also offered a means for imperial subjects across the Empire to participate in its victory. Emperors and provincial leaders produced spectacles in order to please the crowds and thus maintain their political power, and the events projected the power of the crowds to demand them.
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The Program: Bleeding and Dying for Power
All of this projection of power centered on spectacles of blood-drenched and painful death that became emblematic of Romanitas. To understand how witnessing these gory entertainments unified and empowered the crowd, it will be helpful first to know what they saw in the spectacles. The program for spectacles at the arena followed a standard format.
Morning: Slaughter of the Beasts
The morning entertainments, the venationes, presented and killed wild animals collected from Rome’s military campaigns at the boundaries of the Empire. The entertainments could include animals pitted against each other as well as human venatores fighting the animals.
Midday: Executions
Animals not slaughtered in the morning venationes could be used in the midday events (meridiani) when executions of condemned criminals and prisoners of war— people considered disposable—were presented in creative ways for the crowd’s entertainment, sometimes with elaborate staging of myths as “snuff plays.” The forms of execution were designed to completely debase the victim. The humiliation distanced members of the audience from the criminal and diminished their potential sympathy for him or her. The audience was thereby assured of a just order of law. As they ridiculed those being executed, members of the audience were united in their sense of moral superiority. Members of the elite classes convicted of capital offenses were not usually subjected to a humiliating public execution but rather were dispatched swiftly, by beheading, for example, at a more secluded location. The “performers” at the midday execution entertainments were defined as disposable “others.”
The event began with bestiarii (animal-handlers) or soldiers leading the condemned into the arena, yoked in twos or threes or tied to stakes or chariots. They usually had very little clothing, men naked or wearing a loincloth, women in a light tunic or skirt and brassiere or sometimes naked. They would be presented to the audience and then displayed on a raised platform bound on a stake or in stocks. Then they would receive the specific method of execution that had been designated for them at their trial.
Many were condemned to the beasts, perhaps with the crowd’s chant of “ad bestias” at their trials. The beasts, including lions, leopards, and bears, were goaded by the bestiarii to “bite, trample, gore, or … to have intercourse with … the victim.”1 The condemned could also be forced to fight one another to the death without protection, with the last one standing killed by some other means.
At this point, if we listen as well as see, we will hear the screams of the victims as well as the roar of the crowd. Our reaction may not be the same as that of the crowd in the arena, however. These spectacles of death were popular, after all, and the crowds reportedly enjoyed them. In watching the executions, members of the audience could identify with those who implemented justice, concurring in the justice of the fate of the condemned and sharing in the power of condemnation, sometimes exercising their will by unison chanting. Other allurements included the fascination of horrific images and the excitement of the unpredictability of wild beasts and other theatrical devices. The spectacles provided not only the basic component of entertainment, an antidote to boredom, but also appealed to the “morbid desire to witness the actual moment of death.”2
The horror of the midday executions also functioned as an effective deterrent for the enforcement of Roman order, yet horror was not the dominant emotion of the crowd. The crowds reacted with pleasure, not revulsion. The spectacle opened a deep chasm between the condemned victims on the sands and the audience behind the podium wall.
Afternoon: Gladiatorial Games
Even before Christian martyrs are reported to have entered the arena, gladiators managed to traverse the gulf between victims and spectators and create a human connection with the audience during the afternoon portion of the program. Like the executions, the gladiatorial combat reserved as the afternoon entertainment was apparently designed to debase its participants. Yet the gladiators themselves appear to have taken up the performance of their ill fate as a means of achieving honor in a performance of Romanitas.
Gladiators fought in pairs, matched by armaments and skill level, according to rules of combat. They normally fought to a conclusion, not a tie. If the loser was not killed or mortally wounded in the combat, when he (or she) was disarmed or immobilized, the loser stopped fighting and signaled submission. This was the dramatic and decisive moment the crowd craved. Waiting in a pause as the games’ “organizer” (the editor) decided the loser’s fate, the crowd would chant its own decision. To spare his life to fight another day, they would chant “Missum!” or wave cloths. To indicate their desire for the final blow that would cut the loser’s throat, they would chant “Iugula!” or raise down-turned thumbs. The editor, or the emperor in the games at Rome, would then give the final signal to please the crowd.
The performance of the losing gladiator in this final decisive moment became an opportunity to demonstrate Roman virtus* and to die in front of a Roman audience in a way that reclaimed the gladiator’s honor and status as a subject with whom the audience would want to identify rather than a disposable object for their entertainment. This decisive moment, with the victorious gladiator holding the blade over the defeated one’s neck awaiting the signal of the editor as the crowd chanted its decision, becomes a focal point in defining Roman culture. This moment, and the figure of the defeated gladiator at the center, are worth more focused attention.
* The Latin virtus, the root of the English “virtue,” is from vir (“man”) and literally means “manliness, maleness.” It connotes those excellences that Roman culture prized as male gender ideals, such as strength, stoic endurance, and courage.
Gladiators: From “Disposables” to Icons
The gladiators held an ambivalent position in the arena. On the one hand, like the beasts and criminals of the first two entertainments of the day, they were forced into mortal combat by their status as “other” and uncivilized non-Romans. On the other hand, they performed the essential virtus that defined Roman identity, a military cultural identity.
Slaves and Captives (Involuntary)
Many gladiators were prisoners of war, whose numbers provided a large supply to be “used up” in lavish spectacles designed as impressive evidence of Rome’s military victories. As fighters in military forces opposing Rome, many of these captives already possessed the skills for combat that were part of the training in the gladiatorial schools. Condemned criminals were another source. While many were sentenced to be executed in the midday spectacles, some received a lesser penalty and were sentenced to the gladiatorial schools. Gladiators who fought well enough to survive might be granted their freedom.
Whatever their origin, the legal status of these gladiators was that of slaves, and they were considered infames, categorized in the occupations of shame, alongside actors, prostitutes, and pimps. As such, they shared aspects of the identity of “disposable” others executed during the midday entertainments. As objects forced to kill or be killed, they contributed to the spectacles’ projection of Roman imperial power.
Yet they became something more.
Icons and Nobles (Voluntary)
According to one informed estimate, as early as the end of the era of the Republic in the late first century BCE, half of the gladiators were volunteers. Evidence of free persons, nobles, and even emperors participating in the arena as gladiators is plentiful. Some apparently entered the arena for a special performance without pay to demonstrate their courage and fighting ability. Others became gladiators as a career choice, fighting for pay. While some apparently volunteered due to impoverishment, others became gladiators for reasons associated with the changing identity of the gladiator. Those who volunteered to be gladiators bound themselves in servitude to a gladiatorial manager, swearing an oath by which they promised to be “burned, bound, beaten, and slain by the sword.”3
Given the many negative associations with the position of the gladiator, we might well ask, “What was it that drew free men to discard community, status, dignity and power to fight in the arena, in the space allotted to the ruined and condemned?”4
A core aspect of the emotional motivation for becoming a gladiator was the opportunity to make the involuntary voluntary. This started with the oath. “The gladiator, by his oath, transforms what had originally been an involuntary act to a voluntary one, and so, at the very moment that he becomes a slave condemned to death, he becomes a free agent and a man with honor to uphold.55 In the same manner, gladiators sought to gain ultimate freedom and honor by performing their death upon defeat as a voluntary action, offering their neck to the blade of the victor and waiting for the editor’s decision at the behest of the crowd. The defeated gladiator’s performance in this decisive moment could persuade the crowd to chant to save him and the editor to comply, thus making a good performance of virtus a more immediate survival strategy as well.
Gladiators sought to gain ultimate freedom and honor by performing their death as a voluntary action.
In the period when the elite classes were losing out as political power was being centralized in the emperor, some sought a gladiatorial “solution” for regaining lost honor. “The importance of the social and psychological role of the gladiator among the free and privileged classes in Rome developed apace with the notion that with the failure of the aristocratic republic, dignitas, social worth, had become a word whose only content was humiliation.”6 Rome was in transition from the warrior culture of the Republican era, when there was something closer to a fair competition between equals, to the ascendency of a culture ruled by a “rogue male” who had become a father figure (the emperor)—a fundamental re-ordering of competition as unequal. Fighting an equal opponent as a gladiator in the arena allowed aristocrats to pursue not only the sex appeal and “rock star” status that famous gladiators attained but also the glory that was being lost as they were becoming a new form of underling in the restructuring of the social order.
The gladiators used their performance of death in the arena to become iconic images of Roman identity. They performed their deaths to conform to what the audience wanted to believe about their own Roman identity and thus created an image of redemption of the honor the elite males were losing. The path the gladiators forged to restore their own honor also became the path for others. In the process, they became icons of Roman virtus. A famous exemplar of this Roman identity and virtus was Mucius Scaevola, a popular hero of the Roman Republic who was held up as emblematic of the Roman way and viewed as a martyr for the cause of Rome. As the story goes, Mucius infiltrated the enemy camp to assassinate King Porsena during his siege of Rome in 508 BCE in the Etruscan wars. He killed the wrong man, however, and was caught. The words the historian Livy puts in his mouth as he is brought before Porsena’s tribunal define his subsequent actions as distinctively Roman.
“I am a Roman citizen (Romanus sum),” he cried; “men call me Gaius Mucius. I am your enemy, and as an enemy I would have slain you; I can die as resolutely as I could kill: both to do and to endure valiantly is the Roman way.” (2.12.8–10)
He then demonstrates “the Roman way” by thrusting his right hand into the fire prepared to burn him and holding his hand there to let it burn up, saying: “Look, that you may see how cheap [the Romans] hold their bodies whose eyes are fixed upon renown (gloriam)!” (2.12.13) Mucius’s action became emblematic of Roman identity and honor.
Gladiators who were originally “disposables” forced into the arena to fight for the onlookers’ entertainment redefined themselves as subjects rather than objects by performing their life-and-death struggle in the Roman way illustrated in the stories of Scaevola—by disposing of themselves in a voluntary action.
The audience is essential. The Roman whose eye is fixed on gloriam, as Livy’s Scaevola puts it, requires an audience to grant the glory, and gladiators sought their gloriam by putting the power of affirmation into the hands of the audience in the arena.7 The image of the gladiator is created in a performative intersection in the arena: the gladiator performs his death to redeem his honor in the eyes of a crowd who identifies with him and desires the performance he offers. What happens to the audience watching this display? Watching the gladiatorial games was considered part of military training, and for those not destined for battle it was a way to participate in the Roman military ethos, an inspiration to live with Roman virtus. In praising the Emperor Trajan’s gladiatorial exhibition, for example, Pliny the Younger says that he produced
nothing spineless or flabby, nothing that would soften or break the manly spirit [animos virorum] of the audience, but a spectacle which inspired the audience to noble wounds and to despise death, since even in the bodies of slaves and criminals the love of praise and desire for victory could be seen.8
In observing the gladiatorial display, then, members of the audience would identify with the gladiators and vicariously experience their virtus.
We might expect that the audience would identify with the victor in this display, yet this was not simply sadistic voyeurism. Philosophers encouraged a focus on the defeated as a learning exercise for facing death. While their encouragement may have been addressed primarily to elites, gladiatorial combat gave spectators a vicarious opportunity to rehearse both the role of the victor and the role of the defeated.
The audience identified with the gladiators and longed for an experience of honor courageously snatched from humiliation. They craved a sense of their own empowerment in witnessing a victim dying invictus (“unconquered”). They viewed with contempt a gladiator who showed unwillingness to die because they felt his shame. A display of weakness would disgust the audience and would be rewarded with chants for his death. A display of courage could lead to chants to spare his life. This vicarious identification with the defeated as well as with the victor made the gladiator into an icon.
We need to see the gladiators as engaged in a performance in which they moved themselves from being made into “others” —uncivilized objects outside of Roman “civilization”—to being subjects who embodied Roman ideals.
We need to see the gladiators, then, as engaged in a performance of death in which they moved themselves from being made into “others”—uncivilized objects outside of Roman “civilization”—to being subjects who embodied Romanitas and Roman virtus, from expendable outsiders to central icons of Roman identity. In the process, they and the crowds for whom they performed used the arena to shape a workable identity for themselves within an imperial social hierarchy that, on some level, made all of them humiliated objects. From a status that historian Orlando Patterson has aptly termed “social death,” the gladiator, especially the defeated one, provided a Roman audience a momentary glimpse of a live human being, defined in terms of Roman cultural currency, by fusing defiance and acquiescence. The crowd vicariously experienced that same moment of freedom in embracing this image of dying invictus, and thus they elevated the gladiator as an icon of their Roman identity. The gladiator, in turn, helped to stabilize the empire by making its humiliations emotionally manageable.
Christian Martyrs in the Arena
Accounts of the Christian martyrs in the arena place them on a similar trajectory from “disposables” to icons of a new form of Roman identity. Christian martyrs entered the arena as a location where the Roman social order was being defined, and the accounts of their trials and deaths offer both a challenge to that order and a redefinition that reinforces it.
Martyr Stories as Social Critique
Recent decades have produced many fine studies of the accounts of the martyrs as social critique, and the martyrs have traditionally been perceived as challenging Roman imperial authority. Without in any way discounting such studies or the social critique they demonstrate, we should note a frequent tendency to uncritically assume a status of Christian exceptionalism for the martyrs. Here, for example, is how one scholar capsulizes the image of the martyr as a social critic:
The spectacle of the arena was centred around a crushing assertion of the right order of society ... In such a society, so pointedly aware of the dynamics of authority and representation, for a Christian to subvert humiliation by embracing death with equanimity would have constituted a powerful social gesture.9
While we need to recognize the power of this social gesture, we should not imagine that it was original. The path to subversion of “humiliation by embracing death with equanimity” was already well-worn by the gladiators and by the tales Romans told themselves about the essence of their identity.
Martyrs as Gladiators
To associate the martyrs and the gladiators is hardly a stretch given that both of their performances of death take place in the Roman arena. Popular traditions also associated the martyrs with athletes and gladiators. Just as people collected oil from the athletes and blood from the gladiators as cures for fever and epilepsy, Christians collected fragments of martyrs’ remains and believed in the relics’ magical properties. Ancient portrayals of both gladiators and martyrs also share a common emphasis on honor, selfactualization, and the voluntary acceptance of death.
Christian writers associate martyrs with athletes and gladiators, as performers who impress an audience with their virtus (nobility, courage, indifference to pain). Ignatius of Antioch, writing to the future martyr Polycarp, exhorts him, “It is like a great athlete to take blows and yet win the fight.”10 Blandina, a female martyr of Lyons, is also described as a “noble athlete.”11 In one of her dreams, the martyr Perpetua envisions herself as an athlete and gladiator in the arena.12
The martyr Germanicus models the Romanitas exemplified by the popular figure of Mucius Scaevola.13 Rather than waiting for the fate to which he has been sentenced, We need to see the gladiators as engaged in a performance in which they moved themselves from being made into “others” —uncivilized objects outside of Roman “civilization”—to being subjects who embodied Roman ideals. The Fourth R 29–5 September–October 2016 8 he seizes hold of it. Like Scaevola thrusting his right hand into the flame and holding it there to burn, Germanicus seizes the beast presented to kill him in the same gesture of Roman identity that the gladiators use by offering their throat upon defeat. In a similar gesture, Perpetua guides the hand of her executioner, a gladiator, to bring the knife to her throat.14
Christian writers also emphasize martyrdom as a voluntary action. For example, Ignatius asserts, “I die willingly for God,” and his oath is patterned after the gladiator’s: “Come fire, cross, battling with wild bears, wrenching of bones, mangling of limbs, crushing of my whole body, cruel torture of the devil—only let me get to Jesus Christ.”15 Ignatius swears the oath, but his enslavement is to a different kind of gladiatorial manager: God and Christ. This transference indicates the reshaping of the arena as the martyrs became central icons for an empire redefined as Christian.
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Differences in the Setting
The accounts of the martyrs portray an arena where a Christian vision of the empire is being constructed around the performances of the iconic martyrs. While the accounts portray the martyrs as gladiators nobly taking their final stand on the sands of the arena, the setting for the martyrs’ combat and performance of death differs significantly from that of the gladiators.
Performance of Death
We have seen that it was during the afternoon program of combat that the gladiators connected with the crowd and in the process moved their identity from despised outsiders to icons of Roman identity. The martyr narratives portray a similar identity shift taking place in the noonday program of executions in a performance that echoes the gladiators’ refusal to accept the “despised other” identity. By voluntarily embracing the death to which they have been sentenced, martyrs reveal themselves in the decisive moment as subjects rather than objects. Narratives about martyrs make a concerted effort to portray the martyrs achieving recognition of their humanity, despite their being forced into a process designed to dehumanize them.
From the viewpoint of the Roman crowd, the Christians were among the criminals and threats to the Roman legal order, the “others” executed during the noonday entertainments. Tacitus (Annals 15.44) describes this “othering” of the Christians under Nero, in spectacles that included putting the hides of beasts on them and letting them be torn apart by dogs, displays that unambiguously portrayed them as inhuman/uncivilized. They were outsiders who deserved destruction, not the fair fight of the afternoon entertainment. They were the noxii, not trained for the fight as the gladiators were.
Combat by Trial
The accounts of the martyrs portray them as gladiators skilled and trained for combat, but the combat takes place at their trials. They are presented as trained to speak eloquently and stand courageously at their trials before Roman authorities. Their prowess is not military skills for a theatrical battlefield, but rhetorical skills and valor to win hearts and minds in a court of opinion beyond the Roman legal system.
In the account of Polycarp’s trial, for example, we can see the acquiescence and defiance of the gladiator that embodies the Roman identity expressed in the popular stories of Mucius Scaevola. Instead of saying, “I am a Roman (Romanus sum) … Look, that you may see how cheap [the Romans] hold their bodies whose eyes are fixed upon renown (gloriam)!” Polycarp, like many of the other martyrs portrayed in the accounts, says, in effect, “I am a Christian (Christianus sum)! See how cheap we hold our bodies whose eyes are fixed upon eternal glory!” Polycarp says, in effect, “See how I am more Roman than the Romans!” This interchange becomes the martyr’s combat scene where victory is won by refusing to be intimidated by the threat of torture and death and by making an involuntary fate voluntary.
The arena performance becomes an extension of the trial. Torture and execution in the “contest” in the arena then becomes another opportunity to provide victorious testimony. Torture was believed to be an effective means of obtaining credible testimony from slaves and people of low rank, people who would be susceptible to pressures exerted by their owners or who would be easy targets for bribery. If such a person did not change his or her testimony under torture, the testimony was certified as true. In the narratives, the tortures and death to which the martyrs are subjected in the arena continue their “witness” and testimony at the trial, but the martyr has been reframed as a “witness under torture” rather than a “criminal under investigation,” and the question of truth has been shifted from the Christian martyr’s guilt to the content of the Christian message. In effect, the narratives put the interrogators on trial before the audience of the text, that is, those who are reading the narrative.
An Arena of Narrative
The narratives depict the martyrs crossing not only the podium wall but also the hostile arena crowd to perform a death scene that connects them to the audience of the text and to a celestial audience, the audience(s) of decisive consequence for their combat/trial. The martyrs portrayed in the accounts hear the acclamations of the celestial audience and fix their eyes on Christ as an editor with the power to grant “favor” beyond the physical arena.16 In this new arena of narrative, the martyrs perform for the celestial audience and “our people” (the audience of the text), not for “those people” in the hostile crowd of the earthly arena. Other early Christian writers envisioned retribution against “those people” in a spectacle of consuming fire at the Day of Judgment envisioned as a new arena with God as the editor/emperor providing the entertainment for the faithful.17
For the new Christian empire, this narrative spectacle program accomplished the edifying and unifying purposes that the physical arena spectacles achieved for the earlier Roman Empire. Like the Roman arena crowds, the audiences of the Christian spectacle texts were offered an opportunity to participate in the divine imperial power of the new arena. Along with the celestial observers, they became the “real audience” who could watch as the Roman officials and the hostile arena crowd become the “other.” They could also identify with the martyr who took the role of the gladiator as the edifying icon for a new form of Roman imperial culture, icons of a Christianized Romanitas and virtus, as an “even more Roman way.” This new icon of the martyr is as complex as the icon of the gladiator, but complex in similar ways.
Like the Roman amphitheater, the Christian literary arena was intended to project imperial power. In the Roman amphitheater, however, a human emperor or his representative was physically present in a physical crowd where a dynamic negotiation of power relations was still possible. The Christian narrative amphitheater, a stage for the performance of the martyrs where Christ and ultimately God hold the position of the emperor, presents a more absolute image of power relations. Iconic portrayals of Christian martyrs who sacrifice themselves completely to God and Christ have a place in an absolutist vision of power relations in a Christianized Roman Empire, a place worth examining in relation to the place occupied by the image of the gladiator in the Roman Empire. 4R
Copyright © 2016 Westar Institute. All rights reserved. May not be reproduced or reprinted without permission in writing from the copyright holder.
Daniel Frayer-GriggsSusan M. (Elli) Elliott (Ph.D., Loyola University Chicago) is Adjunct Instructor in Humanities at Northwest College in Powell, Wyoming. A writer and lecturer based in Red Lodge Montana, her book Family Empires is forthcoming in 2017.
1. Potter, “Martyrdom,” 66.
2. Coleman, “Fatal Charades,” 58–59.
3. “uri, vinciri, verberari, ferroque, necari patior” (Petronius, Satyricon, 117; Seneca, Moral Epistles, 71.23); in Barton, Sorrows, 14.
4. Barton, Sorrows, 26.
5. Barton, Sorrows, 15.
6. Barton, Sorrows, 27.
7. Barton, Sorrows, 34.
8. Barton, Sorrows, 21, citing Pliny the Younger, Panegyricus 33.1.
9. Cooper, “The Voice of the Victim,” 148.
10. Letter to Polycarp 3.1
11. Martyrs of Lyons 19.
12. Martyrdom of Perpetua 10.
13. Martyrdom of Polycarp 3.
14. Martyrdom of Perpetua 21.9.
15. Letter to the Romans 4.1.
16. Letter to Polycarp 2, 9; and Martyrdom of Perpetua 18
17. Letter to Polycarp 11, Tertullian De Spectaculis 30, and Edwards, Death in Ancient Rome, 214 citing Augustine, Enarrationes in psalmos 39.9.
Works Cited
Barton, Carlin A. The Sorrows of the Ancient Romans: The Gladiator and the Monster. Princeton University Press, 1993.
Coleman, K. M. “Fatal Charades: Roman Executions Staged As Mythological Enactments.” Journal of Roman Studies 80 (1990) 44–73.
Cooper, Kate. “The Voice of the Victim: Gender, Representation and Early Christian Martyrdom.” Bulletin of the John Rylands University Library of Manchester 80,3 (1998) 147–58.
Edwards, Catharine. Death in Ancient Rome. Yale University Press, 2007.
Potter, David. “Martyrdom as Spectacle.” Pp. 53–88 in Theater and Society in the Classical World. Ed. Ruth Scodel. University of Michigan Press, 1993.
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Monday, December 01, 2008
Stereotypes: Shakespeare's character called Shylock the Jew
Shylock is a central character in Shakespeare's The Merchant of Venice who famously demanded a pound of flesh from the title character.
There are elements of humanity in the character, says Wikipedia, most notably in his legendary "Hath not a Jew eyes" speech, in which he argues his right to dignity and to revenge himself on the Christians who wrong him. This passage is also often thought to be a breakdown of the division between Jews and Christians, as both will seek revenge.
In modern performances of The Merchant of Venice, Shylock is often treated as a tragic figure, while Antonio is cast as more of a villain.
Not mentioned in the play (but well known to his first audiences) is that during Shakespeare's day, money lending was one of the few careers open to Jews, since Jews were forbidden to charge interest to their brethren (fellow Jews), and Christians also followed Old Testament laws condemning usury charged to their brethren (fellow Gentiles). There was therefore a brisk business in banking between Jews and Christians.
Of particular note is that Jews were almost universally detested by Christian nations in the 16th Century, and England had expelled all Jews some 300 years prior to Shakespeare's time. Much of what remained of them were tales fraught with anti-Semitic sentiments ranging from exaggeration to outright lies, which depicted them as vile and despicable. Despite Shakespeare's upbringing in such an environment, he still managed to portray Shylock as a human being.
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In what ways does the modern era allow the monster more or less agency? Refer to the novel Frankenstein and The Tempest.
Expert Answers
Michael Foster eNotes educator| Certified Educator
Agency is a term that describes a character’s ability to make his own choices, given the confines of his environment.
In Frankenstein, the creature is initially given free agency to make choices but is eventually limited by the society’s reaction to him. This is Shelley’s understanding of the concept of tabula rasa, or “blank slate,” in which a child is born free from any specific kind of human nature. In effect, people are born “good” but are turned “evil” by the society around them. The creature, who is immediately abandoned by his creator at his “birth,” seeks only good around him. His assumption is that people are friendly and welcoming until he faces repeated rejection. He then has the choice to turn “bad” and sets out on a murdering spree as a result of what he has learned. Thus agency can be seen in this work as morally neutral to begin with, in connection with the concept of tabula rasa.
In The Tempest, Caliban has no agency, at least physically. He is under the complete control of Prospero and must do what the sorcerer commands. He does exhibit the choice to decide how he is going to internally respond to these commands. He mentally rebels while he physically obeys. He is finally released and given complete freedom.
In the modern era, the reading of these works allows us to see that the characters have agency as to the matter of personal choice as opposed to being subject to divine destiny or predestination. In humanism, the emphasis is on people's choices to control their lives, rather than being controlled by God (much like Prospero's control of Caliban). In Frankenstein, we can see the beginning of a more modern perspective in the matter of agency. While the creator (Frankenstein) has rejected his creation, beginning in the 18th century humankind began to reject or redefine their control by God. We have changed from Caliban to the Creature. We may not be able to control our circumstances, but we can always control, for good or for evil, our response to our circumstances.
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<urn:uuid:752eb1ba-8352-4c63-92e5-d198828cb90a>
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{
"dataset": "HuggingFaceTB/dclm-edu",
"edu_int_score": 4,
"edu_score": 3.5625,
"fasttext_score": 0.13628530502319336,
"language": "en",
"language_score": 0.9727456569671631,
"url": "https://www.enotes.com/homework-help/what-ways-modern-era-allow-monster-more-less-711014"
}
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hypervelocity impact
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Quick Reference
The impact of an object into a target at a speed that greatly exceeds the speed of sound in the struck body. Typically, in solids, this limit occurs at around 4 km/s. At these speeds solid rock behaves like a fluid. Hypervelocity impacts produce craters that are generally circular, and far larger than the impacting body.
Subjects: Astronomy and Astrophysics.
Reference entries
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<urn:uuid:3088a6ac-52f2-4e68-984e-3e247f1c27f7>
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{
"dataset": "HuggingFaceTB/dclm-edu",
"edu_int_score": 4,
"edu_score": 3.5625,
"fasttext_score": 0.41367053985595703,
"language": "en",
"language_score": 0.8651459813117981,
"url": "http://oxfordindex.oup.com/view/10.1093/oi/authority.20110803095954200"
}
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Italy exerted a powerful attraction on northern European artists from the 16th century on. Many of them travelled to Italy as part of their artistic training. They went there to study the art of antiquity, the Renaissance and of their own time. These painters were called ‘Italianates’. The first generation of northerners captured Italian folklife in genre scenes with marked contrasts of light and dark. Later Italianates concentrated on the surroundings and painted landscapes with mountains, ruins and groups of people or animals, all bathed in golden sunlight.
Most of the Dutch and Flemish Italianiates concluded their journey in Rome. There, in 1623, they founded an artists’ fraternity, the ‘Bent’ (band of painters). Its members, called ‘Bentveughels’ (birds of a feather), were subject to a rite of initiation and given a nickname. Well-known Bentveughels are Cornelis van Poelenburch, Jan Asselijn, Jan Both, Jean Baptiste Weenix and Herman van Swanevelt. Inspired by them, painters in the Netherlands began working in the same style without ever having set foot in Italy.
timeline stijlen by Peter Kooke
April 6 2013 - 178 works
Italy , in dutch painters eye by PhotoComix
August 26 2013 - 10 works
Tekeningen by D.Schreuder
September 8 2013 - 23 works
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<urn:uuid:99edd905-01d0-4f4b-a044-0b36ee380333>
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{
"dataset": "HuggingFaceTB/dclm-edu",
"edu_int_score": 4,
"edu_score": 3.609375,
"fasttext_score": 0.03311491012573242,
"language": "en",
"language_score": 0.9448160529136658,
"url": "https://www.rijksmuseum.nl/en/explore-the-collection/styles/italianates"
}
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KEEPING clean was a novel idea two centuries ago. The demand for laundry grew out of the discovery, in the 19th century, of links between dirt and disease, and from the emergence of clean clothes as a sign of social superiority.
Accessible water and hedges on which to hang things out to dry made the whole business of washing clothes much easier in rural villages. In cities, home launderers had to contend with a shortage of water as well as an abundance of smuts that settled on drying clothes. That led to the rise of the steam laundry, a business that in both Britain and America gave employment to thousands of women.
Thanks to William Strutt, who appears to have invented the first mechanical laundry (and so surely deserves a statue in his honour), these businesses hoped to emulate the efficiency of the factories that were beginning to mass-produce consumer goods. But they largely failed to reap economies of scale. Individual clothes need different treatments; and locating one lost collar in a thousand is harder than locating one in a hundred.
Laundry has always been a business that the poor can do from home. That held down wages. In time, the washers began to demand a decent wage and trade unions helped them organise to get it. But what killed the commercial laundry was the coming of the domestic washing machine, and reliable water and electricity supplies to run it. Even though the laundry owners warned women that they would be scalped in their wringers if they tried to do their laundry at home, the lure of the machine was too great.
It is true that the pictures of ancient washing machines and toiling launderers have a certain delicious nostalgia. However, this book—an expanded version of an academic study published four years ago by Arwen Mohun, a history professor at the University of Delaware—would have benefited from a chart or two, to compare the costs of home and commercial washing and changing pay rates. And it should have mentioned both the cataclysmic impact of the nylon shirt on the business and the survival of the dry-cleaner. Both, in their way, shaped society—as surely as the steam laundry did in an earlier century.
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<urn:uuid:2504126d-0585-4738-bfd0-84d856db2edb>
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{
"dataset": "HuggingFaceTB/dclm-edu",
"edu_int_score": 4,
"edu_score": 3.75,
"fasttext_score": 0.08676260709762573,
"language": "en",
"language_score": 0.9810372591018677,
"url": "http://www.economist.com/node/1748496"
}
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