:: wikimiki.org ::

Harry Moses Horwitz

Harry Moses Horwitz

Perhaps most famous for his black sugar-bowl haircut and prominent eyebags, Moe Howard (June 19, 1897 – May 4, 1975)--born Harry Moses Horwitz--was the "leader" of the Three Stooges. The distinctive coiffe came about when he was a boy and cut off his curls with a scissors, producing a ragged shape approximating a helmet. In many of the shorts they made, he was often portrayed as bullying and domineering the other Stooges, but often ended up being the ultimate victim himself. One of his most popular forms of bullying was his two fingered (simulated) poke in the eye. His other method of keeping the other stooges in line was a slap to the face. Both actions were accompanied by off-screen sound effects, so they appeared much more violent than they were. In real life, Moe Howard was a kind and sensitive person who was greatly saddened by the loss of his brothers Curly and Shemp at a relatively young age. Through it all, he maintained a sense of humor and comic timing that served him throughout his career and life. Howard was married to a cousin of magician Harry Houdini, whom he was devoted to for many years. Wise investments during and after his time with the Stooges allowed him to live comfortably well after his carreer in Hollywood ended. In a 2000 TV movie, Moe was played by Paul Ben-Victor.

External links

- [http://www.3-stooges.com/text/moe.html Biography at 3-stooges.com]
- [http://web2.airmail.net/willdogs/ My Pal Moe by Bob Bernet] (featuring letters and rare photos of Moe Howard at home) Howard, Moe Howard, Moe Howard, Moe Howard, Moe Howard, Moe Howard, Moe Howard, Moe Howard, Moe

Sugar

:This article deals with sugar as food and as an important, widely traded commodity. The word also has other uses; see sugar (disambiguation). In general use, "sugar" is taken to mean sucrose, also called "table sugar" or saccharose, a disaccharide which is a white crystalline solid. It is the most commonly used sugar for altering the flavor and properties (such as "mouthfeel", preservation, and texture) of beverages and food. Table sugar is commercially extracted from either sugar cane or sugar beet. The "simple" sugars, or monosaccharides, such as glucose (which is produced from sucrose by enzymes or acid hydrolysis), are a store of energy which is used by biological cells. A sugar is denoted by any word on the ingredient list that ends with "ose". For information on the other sugars, see monosaccharide and disaccharide. In precise culinary terms, sugar is a type of food associated with one of the primary taste sensations, that of sweetness.

Production

primary taste Table sugar or sucrose is extracted from plant sources. The most important two sugar crops are sugarcane (Saccharum spp.) and sugar beets (Beta vulgaris), in which sugar can account for 12%–20% of the plant's dry weight. Some minor commercial sugar crops include the date palm (Phoenix dactylifera), sorghum (Sorghum vulgare), and the sugar maple (Acer saccharum). In the financial year 2001/2002, 134.1 million tonnes of sugar were produced worldwide. The major cane sugar producing countries are countries with warm climates, such as Australia, Brazil, and Thailand. In 2001/2002 there was over twice as much sugar produced in developing countries as in developed countries. The greatest quantity of sugar is produced in Latin America, the United States and the Caribbean nations, and in the Far East. The sugar beet regions are in cooler climates: North West and Eastern Europe, Northern Japan, plus some areas in the United States including California. The beet growing season ends with the start of harvesting around September. Harvesting and processing continues until March in some cases. The duration of harvesting and processing is influenced by the availability of processing plant capacity, and weather - harvested beet can be laid up until processed but frost damaged beet becomes effectively unprocessable. The world's second largest sugar exporter is the EU. The Common Agricultural Policy of the EU sets maximum quotas for members production to match supply and demand, and a price. Excess production quota is exported (approx 5 million tonnes in 2003). Part of this is "quota" sugar which is subsidised from industry levies, the remainder (approx half) is "C quota" sugar which is sold at market price without subsidy. These subsidies and a high import tariff make it difficult for other countries to export to the EU states, or compete with it on world markets. The U.S. sets high sugar prices to support its producers with the effect that many sugar consumers have switched to corn syrup (beverage manufacturers) or moved out of the country (candy makers). The sugar market is also under attack from the cheap prices of glucose syrups produced from wheat and corn (maize). In combination with artificial sweeteners, drink manufacturers can produce very low cost products.

Cane

The harvested vegetable material is crushed, and the juice is collected and filtered. The liquid is then treated (often with lime) to remove impurities, this is then neutralized with sulfur dioxide. The juice is then boiled, sediment settles to the bottom and can be dredged out, scum rises to the surface and this is skimmed off. The heat is removed and the liquid crystallises, usually while being stirred, to produce sugar which can be poured into moulds. A centrifuge can also be used during crystallization.

Beet

The washed beet is sliced, and the sugar extracted with hot water in a 'diffuser'. Impurities are precipitated with an alkaline solution "milk of lime" and carbon dioxide from the lime kiln. After filtration the juice is concentrated by evaporation to a content of about 70% solids. The sugar is extracted by controlled crystallisation. The sugar crystals are removed by a centrifuge and the liquid recycled in the crystalliser stages. Liquid from which no more sugar can be economically removed is lost from the process as molasses and used in cattle food. The white sugar produced is sieved into different grades for selling.

Cane versus Beet

There is little perceptible difference between sugar produced from beet and that from cane. Testing for impurities can distinguish the two, and these have been developed to reduce fraudulent abuse of EU subsidies, and also aid detection of adulteration of fruit juice. The residues of sugar production differ substantially and from place to place. While Cane molasses can be used as an ingredient that from sugar beet is unpalatable and generally used for industrial fermentation or as animal feedstuff. Cane and beet pulp can be burnt for fuel, but beet pulp is generally dried, pelleted and used as an animal feedstuff.

Types of culinary sugar

Raw sugars are yellow to brown sugars made from clarified cane juice boiled down to a crystalline solid with minimal chemical processing. Raw sugars are produced in the processing of sugar beet juice but only as intermediates en route to white sugar. Types of raw sugar available as a specialty item outside the tropics include demerara, muscovado, and turbinado. Mauritius and Malawi are significant exporters of such specialty sugars. Raw sugar is sometimes prepared as loaves rather than as a crystalline powder: in this technique, sugar and molasses are poured together into molds and allowed to dry. The resulting sugar cakes or loaves are called jaggery or gur in India, pingbian tong in China, and panela, panocha, pile, and piloncillo in various parts of Latin America. Mill white sugar, also called plantation white, crystal sugar, or superior sugar, is raw sugar whose colored impurities have not been removed, but rather bleached white by exposure to sulfur dioxide. This is the most common form of sugar in sugarcane growing areas, but does not store or ship well; after a few weeks, its impurities tend to promote discoloration and clumping. Blanco directo is a white sugar common in India and other south Asian countries. In producing blanco directo, many impurities are precipitated out of the cane juice by using phosphatation a treatment with phosphoric acid and calcium hydroxide similar to the carbonatation technique used in beet sugar refining. In terms of sucrose purity, blanco directo is more pure than mill white, but less pure than white refined sugar. White refined sugar is the most common form of sugar in North America and Europe. Refined sugar can be made by dissolving raw sugar and purifying it with a phosphoric acid method similar to that used for blanco directo, a carbonatation process involving calcium hydroxide and carbon dioxide, or by various filtration strategies. It is then further decolorized by filtration through a bed of activated carbon or bone char depending on where the processing takes place. Beet sugar refineries produce refined white sugar directly without an intermediate raw stage. White refined sugar is typically sold as granulated sugar, which has been dried to prevent clumping. Granulated sugar is available in various crystal sizes, for home and industrial use depending on the application:
- Coarse-grained sugars, such as sanding sugar are favored for decorating cookies (biscuits) and other desserts.
- Normal granulated for table use is typically around 0.5 mm across
- Finer grades are produced by selectively sieving the granulated sugar.
- caster (0.35 mm) which is commonly used in baking
- superfine sugar, and are favored for sweetening drinks or preparing meringue.
- Finest grades
- Powdered sugar, confectioner's sugar (0.060 mm), or icing sugar (0.024 mm), are produced by grinding sugar to a fine powder. A small amount of anti-caking agent to prevent clumping may be added, this is either cornstarch (1%-3%) or tri-calcium phosphate. There are also sugar cubes for convenient consumption of a normal amount. Brown sugars are obtained in the late stages of sugar refining, when sugar forms fine crystals with significant molasses content, or by coating white refined sugar with a cane molasses syrup. Their color and taste become stronger with increasing molasses content, as does their moisture retaining properties. They are also prone to hardening if exposed to the atmosphere although this is reversible.

Chemistry

In biochemistry, a sugar is the simplest molecule that can be identified as a carbohydrate. These include monosaccharides and disaccharides, trisaccharides and the oligosaccharides; these being sugars composed of 1, 2, 3 or more units. Sugars contain either aldehyde groups (-CHO) or ketone groups (C=O), where there are carbon-oxygen double bonds, making the sugars reactive. Most sugars conform to (CH₂O)_n where n is between 3 and 7. A notable exception is deoxyribose, which as the name suggests is "missing" an oxygen. As well as being classified by their reactive group, sugars are also classified by the number of carbons they contain. Derivatives of trioses (C₃H₆O₃) are intermediates in glycolysis. Pentoses ( 5 carbon sugars) include ribose and deoxyribose, which are present in nucleic acids. Ribose is also a component of several chemicals that are important to the metabolic process, including NADH and ATP. Hexoses ( 6 carbon sugars) include glucose which is a universal substrate for the production of energy in the form of ATP. Through photosynthesis plants produce glucose which is then converted for storages as an energy reserve in the form of other carbohydrates such as starch, or as in cane and beet as sucrose. Many pentoses and hexoses are capable of forming ring structures. In these closed-chain forms the aldehyde or ketone group is not free, so many of the reactions typical of these groups cannot occur. Glucose in solution exists mostly in the ring form at equilibrium, with less than 0.1% of the molecules in the open-chain form. Monosaccharides in a closed-chain form can form glycosidic bonds with other monosaccharides, creating disaccharides, such as sucrose, and polysaccharides such as starch. Glycosidic bonds must be hydrolysed or otherwise broken by enzymes before such compounds can be used in metabolism. After digestion and absorption the pricipal monosaccharieds present in the blood and internal tissues are: glucose, fructose, and galactose. The term "glyco-" indicates the presence of a sugar in an otherwise non-carbohydrate substance: for example, a glycoprotein is a protein to which one or more sugars are connected. Simple sugars include sucrose, fructose, glucose, galactose, maltose, lactose and mannose. As far as disaccharides are concerned, the most common are sucrose (cane or beet sugar - made from one glucose and one fructose), lactose (milk sugar - made from one glucose and one galactose) and maltose (made of two glucoses). The formula of these disaccharides is C₁₂H₂₂O₁₁. Sucrose can be converted by hydrolysis into a syrup of fructose and glucose, producing what is called invert sugar. This resulting syrup is sweeter than the original sucrose, and is useful for making confections sweeter and softer in texture.

History

Sugarcane is a tropical grass, probably native to New Guinea. In the course of prehistory, its culture spread throughout the Pacific Islands and into India. By 800 B.C., it was being grown in China as well. Westerners discovered sugarcane in the course of military expeditions into India. Nearchos, one of Alexander the Great's commanders, described it as "a reed that gives honey without bees." Originally, the cane was chewed raw to extract its sweetness. Sugar refining was developed in the Middle East, India and China, where it became a staple of cooking and desserts. In early refining methods, the cane was ground or pounded to extract the juice, and the juice then boiled down or dried in the sun to yield sugary solids that resembled gravel. The Sanskrit word for sugar (sharkara), also means gravel. Similarly, the Chinese term for table sugar is "gravel sugar" (Traditional Chinese:砂糖)。 Later sugar spread to other areas of the world through trade. It arrived in Europe with the arrival of the Moors. Crusaders also brought sugar home with them after their campaigns in the Holy Land, as there they encountered caravans carrying this "sweet salt" as it was called. While sugar cane could not be grown in northern Europe, sugar could be extracted from certain beets and these began to be widely cultivated around 1801, after the British control of the seas during the Napoleonic wars isolated mainland Europe from the Caribbean.

The history of sugar in the West

In the 1390s, a better press, which doubled the juice obtained from the cane, was developed. This permitted economic expansion of sugar plantations to Andalusia and the Algarve. In the 1420s, sugar was carried to the Canary Islands, Madeira and the Azores. In 1493, Christopher Columbus stopped, intending to stay only four days, at Gomera in the Canary Islands, for wine and water. Columbus became romantically involved with the Governor of the Island, Beatrice. He stayed a month. When he finally sailed she gave him cuttings of sugarcane, the first to reach the New World. The Portuguese took sugar to Brazil. Hans Staden, published in 1555, writes that by 1540 there were 800 sugar mills on Santa Catalina Island and another 2000 up the north coast of Brazil, Demarara and Surinam. Approximately 3000 small mills built before 1550 in the New World created an unprecedented demand for cast iron gears, levers, axles and other implements. Specialist trades in mold making and iron casting were inevitably created in Europe by the expansion of sugar. Sugar mill construction is the missing link of the technological skills needed for the Industrial Revolution that is recognized as beginning in the first part of the 1600s. After 1625, the Dutch carried sugarcane from South America to the Caribbean islands from Barbados to the Virgin Islands. In the years 1625 to 1750, sugar was worth its weight in gold. Price declined slowly as production became multi-sourced especially through British colonial policy. Sugar production also increased in the American Colonies, Cuba, and Brazil. African slaves became the dominant plantation worker as they were resistant to the diseases of malaria and yellow fever. European indentured servants were in shorter supply, succeptible to disease and a less economic investment. Local Native Americans had been reduced by European diseases like smallpox. With the European colonization of the Americas, the Caribbean became the world's largest source of sugar. Sugar cane could be grown on these islands using slave labour at vastly lower prices than cane sugar imported from the East. Thus the economies of entire islands such as Guadaloupe and Barbados were based on sugar production. The largest sugar producer in the world, by 1750, was the French colony known as Saint-Domingue, which is today the independent country of Haiti. Jamaica was another major producer in the 1700s. During the eighteenth century, sugar became enormously popular and went through a series of booms. The main reason for the heightened demand and production of sugar was a great change in the eating habits of many Europeans. For example, they began consuming jams, candy, tea, coffee, cocoa, processed foods, and other sweet victuals in much greater numbers. Reacting to this increasing craze, the islands took advantage of the situation and began harvesting sugar in extreme amounts. In fact, they produced up to ninety percent of the sugar that the western Europeans consumed. Of course some islands were more successful than others when it came to producing the product. For instance, Barbados and the British Leewards can be said to have been the most successful in the production of sugar because it counted for ninety-three and ninety-seven percent of the island’s exports, respectively. Planters later began developing ways to boost production even more. For example, they began using more animal manure when growing their crops. They also developed more advanced mills and began using better types of sugar cane. Despite these and other improvements, the prices of sugar reached soaring heights, especially during events such as the revolt against the Dutch and the Napoleonic wars. Sugar was a highly desired product, and the islands knew exactly how to take advantage of the situation. As Europeans established sugar plantations on these larger Caribbean islands, prices fell, especially in Britain. What had previously been a luxury good began, by the eighteenth century, to be commonly consumed by all levels of society. At first most sugar in Britain was used in tea, but later candies and chocolates became extremely popular. Sugar was commonly sold in solid cones and required a sugar nip, a pliers-like tool, to break off pieces. Sugar cane quickly exhausts the soil and larger islands with fresher soil were pressed into production in the nineteenth century. For example, it was in this century that Cuba rose as the richest land in the Caribbean (with sugar being its dominant crop) because it was the only major island that was free of mountainous terrain. Instead, nearly three-quarters of its land formed a rolling plain which was ideal for planting crops. Cuba also prospered above other islands because they used better methods when harvesting the sugar crops. They had been introduced to modern milling methods such as water mills, enclosed furnaces, steam engines, and vacuum pans. All these things increased their production and production rate. After the world's only successful slave revolution established the independent nation of Haiti, sugar production in that country declined and Cuba replaced Saint-Domingue as the world's largest producer. Production spread to South America as well as to new European colonies in Africa and the Pacific.

The rise of beet

In 1747 the German chemist Andreas Marggraf identified sucrose in beet root. This discovery remained a mere curiosity for some time, but eventually his student Franz Achard built a sugarbeet processing factory at Cunern in Silesia, under the patronage of Frederick William III of Prussia. While never profitable, this plant operated from 1801 until being destroyed during the Napoleonic Wars. Napoleon, cut off from Caribbean imports by a British blockade and at any rate not wanting to fund British merchants, banned sugar imports in 1813. The beet sugar industry that emerged in its place grew, and today, cane and beet sugar enjoy approximately equal world production. While it is no longer grown by slaves, sugar growing in developing countries continues to this day to be associated with workers earning minimal wages and living in extreme poverty. Cuba was a large producer of sugar in the 20th century until the collapse of the Soviet Union took away their export market and the industry collapsed. In the developed countries, the sugar industry is machine reliant, with a low requirement for manpower. A large beet refinery producing around 1,500 tonnes of sugar a day needs a permanent workforce of about 150 for 24 hour production.

Mechanization

Beginning in the late 18th century, sugar production became increasingly mechanized. The steam engine was first used to power a sugar mill in Jamaica in 1768, and soon thereafter, steam replaced direct firing as the source of process heat. In 1813, the British chemist Edward Charles Howard invented a sugar refining method in which the cane juice was boiled not in an open kettle, but in a closed vessel heated by steam and held under partial vacuum. At reduced pressure, water boils at a lower temperature, and this development both saved fuel and reduced the amount of sugar lost through caramelization. Further gains in fuel efficiency were achieved through the multiple-effect evaporator, designed by the African-American engineer Norbert Rillieux perhaps as early as the 1820s, although the first working model was not built until 1845. This system consisted of a series of vacuum pans, each held at a lower pressure than the previous. The vapors from each pan were used to heat the next, and little heat wasted. Today, multiple-effect evaporators are employed widely in many industries for evaporating water. The process of separating the crystallized sugar from the molasses also received mechanical attention: the centrifuge was first applied to this task by David Weston in Hawaii in 1852. written by a swedish guy

Health concerns

In 2003, a report was commissioned by four U.N. agencies, the World Health Organization (WHO) and the Food and Agriculture Organization (FAO), compiled by a panel of 30 international experts. It stated that sugar should not account for more than 10% of a healthy diet. However, the Sugar Association[http://www.sugar.org/] of the US insists that other evidence indicates that a quarter of our food and drink intake can safely consist of sugar. There is an on-going argument as to the value of extrinsic sugar (sugar added to food) compared to that of intrinsic (sugar, seldom sucrose, naturally present in food). In the United States sugar has also been attributed as a leading cause of diabetes and obesity. As stated in the Diabetes in America, 2nd Edition [http://diabetes.niddk.nih.gov/dm/pubs/america/contents.htm] more and more children at younger ages are becoming victims of this deadly disease.

Sugar and hyperactivity

There is common belief among the general public that eating too much sugar (not only sucrose, but other varieties such as glucose) will cause some children to become hyperactive—giving rise to the term "sugar high". Recent studies have not shown a link between the consumption of sugar and hyperactivity levels, even when the researchers focused on children with a presumed "sugar-sensitivity" [http://www.ccmr.cornell.edu/education/ask/?quid=241]. The belief in the possibility of a sugar-high among parents and teachers may cause them to perceive children being more energetic and excited after consumption of sweets and sugary beverages through observer bias. Others believe that the hyperactive effects of sugar can be seen equally in children and adults. Facts have shown that sugar is very addictive and that on average Americans eat or drink 5 pounds of sugar a month, drastically higher than 10 years ago due to the fact that sugar is hidden in many foods under many different names, even in ketchup.

Sugar economics

In many industrialized countries, sugar is among the most heavily subsidized agricultural products. The European Union, the United States, and Japan all maintain elevated price floors for sugar through subsidizing domestic production and imposing high tariffs on imports. In recent years, sugar prices in these countries have been three times the price on the international market. In international trade bodies, especially the World Trade Organization, the "G20" countries led by Brazil have argued that because their cane sugar exports are essentially excluded from these sugar markets, they receive lower prices than they would under free trade. While both the European Union and United States maintain trade agreements whereby certain developing and least-developed countries (LDCs) can sell certain quantities of sugar into their markets, free of the usual import tariffs, countries outside these preferred trade regimes have complained that these arrangements violate the "most favored nation" principle of international trade. In 2004, the WTO sided with a group of cane sugar exporting nations led by Brazil, and ruled that the EU sugar regime and the accompanying ACP-EU Sugar Protocol, whereby a group of African, Caribbean, and Pacific countries are given preferential access to the European sugar market, are illegal. In response, the European Commission proposed on 22 June 2005 to radically reform the EU sugar regime, cutting prices by 39% and eliminating all EU sugar exports. The African, Caribbean, Pacific and Least developed country sugar exporters have reacted with dismay to the EU sugar proposals, arguing for a fairer reform of the EU regime which would be pro-development and meaningful towards the achievement of the Millennium Development Goals. Small quantities of sugar, especially speciality grades of sugar, are sold as 'fair trade' commodities; these products are produced and sold with the understanding that a larger-than-usual fraction of the revenue supports small farmers in the developing world.

References

- A C Hannah,

External links

- [http://www.sugar.ca/index.htm Wide range of information about sugars, from the Canadian Sugar Institute, a non-profit trade association of Canada's refined sugar manufacturers.]
- [http://www.ldcsugar.org/ Least Developed Countries sugar site]
- [http://www.acpsugar.org/ African, Caribbean and Pacific sugar exporters]
- [http://www.who.int/mediacentre/releases/2003/pr20/en/ Expert Report on diet and chronic disease (WHO/FAO)]
- [http://www.sugartraders.co.uk/ Sugar Traders Association of the UK]
- [http://europa.eu.int/comm/agriculture/markets/sugar/index_en.htm European Union sugar regime proposals]
- [http://www.wto.org/english/tratop_e/dispu_e/dispu_status_e.htm#265 WTO ruling on EU sugar regime]
- [http://www.fas.usda.gov/itp/imports/ussugar.asp US Sugar Import Program]
- [http://www.foodsubs.com/Sweeten.html Cook's Thesaurus: Sugar (www.foodsubs.com)]
- [http://www.zucker.prv.pl/ The word "sugar" in more than 220 languages.]
- [http://www.joyfulaging.com/Sugar.htm Sugar Accelerates Aging] Category:Carbohydrates Category:Sweeteners Category:Nutrition Category:Granular materials ja:糖 simple:Sugar zh-min-nan:Thn̂g

Eye

: This article refers to the sight organ. See Eye (disambiguation) for other usages An eye is an organ that detects light. Different kinds of light-sensitive organs are found in a variety of creatures. The simplest eyes do nothing but detect whether the surroundings are light or dark. More complex eyes are used to provide the sense of vision. Many complex organisms including some mammals, birds, reptiles and fish have two eyes which may be placed on the same plane to be interpreted as a single three-dimensional "image" (binocular vision), as in humans; or on different planes producing two separate "images" (monocular vision), such as in rabbits and chameleons.
Varieties of eyes
chameleon chameleon]] In most vertebrates and some mollusks the eye works by allowing light to enter it and project onto a light-sensitive panel of cells known as the retina at the rear of the eye, where the light is detected and converted into electrical signals, which are then transmitted to the brain via the optic nerve. Such eyes are typically roughly spherical, filled with a transparent gel-like substance called the vitreous humour, with a focusing lens and often an iris which regulates the intensity of the light that enters the eye. The eyes of cephalopods, fish, amphibians, and snakes usually have fixed lens shapes, and focusing vision is achieved by telescoping the lens (similar to how a camera focuses). Compound eyes are found among the arthropods and are composed of many simple facets which give a pixelated image (not multiple images as is often believed). Each sensor has its own lens and photosensitive cell(s). Some eyes have up to 28,000 such sensors, which are arranged hexagonally, and which can give a full 360 degree field of vision. Compound eyes are very sensitive to motion. Some arthropods (many Strepsiptera) have compound eye composed of a few facets each with a retina capable of creating an image, which does provide muliple image vision. With each eye viewing a different angle, a fused image from all the eyes is produced in the brain providing a very wide angle high resolution image. Trilobites, which are now extinct, had unique compound eyes. They used clear calcite crystals to form the lenses of their eyes. In this, they differ from most other arthropods, which have soft eyes. The number of lenses in such an eye varied, however: some trilobites had only one, and some had thousands of lenses in one eye. Some of the simplest eyes, called ocelli, can be found in animals like snails, who can not actually "see" in the common sense. They do have photosensitive cells, but no lens and no other means of projecting an image onto these cells. They can distinguish between light and dark (day and night), but no more. This enables snails to keep out of direct sunlight. Jumping spiders have simple eyes that are so large, supported by an array of other smaller eyes, that they can get enough visual inputs to hunt and pounce on their prey. Some insect larvae like caterpillars have a different type of single eye (stemmata) which gives a rough image.
Evolution of eyes
How a complex structure like the projecting eye could have evolved is often said to be a difficult question for the theory of evolution. Darwin famously treated the subject of eye evolution in his Origin of Species: :To suppose that the eye, with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest possible degree. Yet reason tells me, that if numerous gradations from a perfect and complex eye to one very imperfect and simple, each grade being useful to its possessor, can be shown to exist; if further, the eye does vary ever so slightly, and the variations be inherited, which is certainly the case; and if any variation or modification in the organ be ever useful to an animal under changing conditions of life, then the difficulty of believing that a perfect and complex eye could be formed by natural selection, though insuperable by our imagination, can hardly be considered real. Despite the precision and complexity of the eye, computer models of eye evolution, developed by Dan-Erik Nilsson and Susanne Pelger, demonstrated that a primitive optical sense organ could evolve into a complex human-like eye within a reasonable period (less than a million years) simply through small mutations and natural selection. Eyes in various animals show adaption to their requirements. For example, birds of prey have much greater visual acuity than humans and some, like diurnal birds of prey, can see ultraviolet light. The different forms of eye in, for example, vertebrates and mollusks are often cited as examples of parallel evolution, suggesting that the development of eyes through evolution might not be so improbable as it might seem. However, the development of the eye is considered to be monophyletic; that is, all modern eyes, varied as they are, have their origins in a proto-eye believed to have evolved some 540 million years ago (Mya).
Anatomy
monophyletic monophyletic The structure of the mammalian eye owes itself completely to the task of focusing light onto the retina. All of the individual components through which light travels within the eye before reaching the retina are transparent, minimising dimming of the light. The cornea and lens help to converge light rays to focus onto the retina. This light causes chemical changes in the photosensitive cells of the retina, the products of which trigger nerve impulses which travel to the brain. Light enters the eye from an external medium such as air or water, passes through the cornea, and into the first of two humours, the aqueous humour. Most of the light refraction occurs at the cornea which has a fixed curvature. The first humour is a clear mass which connects the cornea with the lens of the eye, helps maintain the convex shape of the cornea (necessary to the convergence of light at the lens) and provides the corneal endothelium with nutrients. The iris, between the lens and the first humour, is a coloured ring of muscle fibres. Light must first pass though the centre of the iris, the pupil. The size of the pupil is actively adjusted by the circular and radial muscles to maintain a relatively constant level of light entering the eye. Too much light being let in could damage the retina, too little light would be blinding. The lens, behind the iris, is a convex, springy disk which focuses light, through the second humour, onto the retina. To clearly see an object far away, the circularly arranged ciliary muscles will pull on the lens, flattening it. Without muscles pulling on it, the lens will spring back into a thicker, more convex, form. Humans gradually lose this flexibility with age, resulting in the inability to focus on nearby objects, which is known as presbyopia. There are other refraction errors arising from the shape of the cornea and lens, and from the length of the eyeball. These include myopia, hyperopia, and astigmatism. On the other side of the lens is the second humour, the vitreous humour, which is bounded on all sides: by the lens, ciliary body, suspensory ligaments and by the retina. It lets light through without refraction, helps maintain the shape of the eye and suspends the delicate lens. Wrapped around these tissues are three layers of tissue surrounding the vitreous humour. The outermost is the sclera which gives the eye most of its white colour. It consists of fibrin connective tissue and both protects the inner components of the eye and maintains its shape. On the inner side of the sclera is the choroid, which contains blood vessels that supply the retinal cells with necessary oxygen and removes the waste products of respiration. Within the eye, only the sclera and ciliary muscles contain blood vessels. The choroid gives the inner eye a dark colour, which prevents disruptive reflections within the eye. The inner most layer of the eye is the retina, containing of the photosensitive rod and cone cells, and neurons. To maximise vision and light absorption, the retina is a relatively smooth (but curved) layer. It does have two points at which it is different; the fovea and blind spot. The fovea is a dip in the retina directly opposite the lens, which is densely packed with cone cells. It is largely responsible for colour vision in humans, and enables high acuity, such as is necessary in reading. The blind spot is a point on the retina where the optic nerve pierces the retina to connect to the nerve cells on its inside. No photosensitive cells exist at this point, it is thus "blind". In some animals, the retina contains a reflective layer (the tapetum lucidum) which increases the amount of light each photosensitive cell perceives, allowing the animal to see better under low light conditions.
Other articles regarding eye anatomy
Aqueous humour, Anterior chamber, Blind spot, Canal of Schlemm, Ciliary body, Ciliary muscle, Cornea, Conjunctiva, Choroid, Fovea, Iris, Lens, Macula, Optic disc, Optic nerve, Ora serrata, Posterior chamber, Pupil, Retina, Sclera, Suspensory ligament, Tapetum lucidum, Trabecular meshwork, Vitreous humour, Zonular fibers.
Cytology
The retina contains two forms of photosensitive cells - rods and cones. Though structurally and metabolically similar, their function is quite different, though they are equally important to vision. Rod cells are highly sensitive to light allowing them to respond in dim light and dark conditions. These are the cells which allow humans and other animals to see by moonlight, or with very little available light (as in a dark room). However, they do not distinguish between colours, and have low visual acuity (a measure of detail). This is why the darker conditions become, the less colour objects seem to have. Cone cells, conversely, need high light intensities to respond and have high visual acuity. Different cone cells respond to different colours (wavelengths) of light, which allows an organism to see colour. The differences are useful; apart from enabling sight in both dim and light conditions, humans have given them further application. The fovea, directly behind the lens, consists of mostly densely-packed cone cells. This gives humans a highly detailed central vision, allowing reading, bird watching, or any other task which primarily requires looking at things. Its requirement for high intensity light does cause problems for astronomers, as they cannot see dim stars, or other objects, using central vision because the light from these is not enough to stimulate cone cells. Because cone cells are all that exist directly in the fovea, astronomers have to look at stars through the "corner of their eyes" where rods also exist, and where the light is sufficient to stimulate cells, allowing the individual to observe distant stars. Rods and cones are both photosensitive, but respond differently to different frequencies of light. They both contain different pigmented photoreceptor proteins. Rod cells contain the protein rhodopsin and cone cells contain different proteins for each colour-range. The process through which these proteins go is quite similar - upon being subjected to electromagnetic radiation of a particular wavelength and intensity (ie. a colour visible light) the protein breaks down into two constituent products. Rhodopsin, of rods, breaks down into opsin and retinal; iodopsin of cones breaks down into photopsin and retinal. The opsin in both opens ion channels on the cell membrane which leads to the generation of an action potential (an impulse which will eventually get to the visual cortex in the brain). This is the reason why cones and rods enable organisms to see in dark and light conditions - each of the photoreceptor proteins requires a different light intensity to break down into the constituent products. Further, synaptic convergence means that several rod cells are connected to a single bipolar cell, which then connects to a single ganglion cell and information is relayed to the visual cortex. Whereas, a single cone cell is connected to a single bipolar cell. Thus, action potentials from rods share neurons, where those from cones are given their own. This results in the high visual acuity, or the high ability to distinguish between detail, of cone cells and not rods. If a ray of light were to reach just one rod cell this may not be enough to stimulate an action potential. Because several "converge" onto a bipolar cell, enough transmitter molecules reach the synapse of the bipolar cell to attain the threshold level to generate an action potential. Furthermore, colour is distinguishable when breaking down the iodopsin of cone cells because there are three forms of this protein. One form is broken down by the particular EM wavelength that is red light, another green light, and lastly blue light. In simple terms, this allows human beings to see red, green and blue light. If all three forms of cones are stimulated equally, then white is seen. If none are stimulated, black is seen. Most of the time however, the three forms are stimulated to different extents - resulting in different colours being seen. If, for example, the red and green cones are stimulated to the same extent, and no blue cones are stimulated, yellow is seen. For this reason red, green and blue are called primary colours and the products of mixing two secondary colours. The secondary colours can be further complimented with primary colours to see tertiary colours.
Acuity
Visual acuity can be measured with several different metrics. Cycles per degree (CPD) measures how much an eye can differentiate one object from another in terms of degree angles. It is essentially no different from angular resolution. To measure CPD, first draw a series of black and white lines of equal width on a grid (similar to a bar code). Next, place the observer at a distance such that the sides of the grid appear one degree apart. If the grid is 1 meter away, then the grid should be about 8.7 millimeters wide. Finally, increase the number of lines and decrease the width of each line until the grid appears as a solid grey block. In one degree, a human would not be able to distinguish more than about 12 lines without the lines blurring together. So a human can resolve distances of about 0.73 millimeters at a distance of one meter. A horse can resolve about 14 CPD (0.62 mm at 1 m) and a rat can resolve about 1 CPD (8.7 mm at 1 m). A diopter is the unit of measure of focus.
Dynamic range
At any given instant, the retina can resolve a contrast ratio of around 100:1 (about 6 1/2 stops). As soon as your eye moves (saccades) it re-adjusts its exposure both chemically and by adjusting the iris. Hence, over time, a contrast ratio of about 1,000,000:1 (about 20 stops) can be resolved.
Adnexa and related parts

The orbit
In many species, the eyes are inset in the portion of the skull known as the orbits or eyesockets. This placement of the eyes helps to protect them from injury.
Eyebrows
In humans, the eyebrows redirect flowing substances (usually rainwater) away from the eye. Water in the eye can alter the refractive properties of the eye and blur vision. It can also wash away the tear fluid, and its beneficial effects, and can damage the cornea, due to osmotic differences between tear fluid and freshwater.
Eyelids
In many animals, including humans, eyelids wipe the eye and prevent the eyes from dehydration. They spread tear fluid on the eyes, which contains substances which help fight bacterial infection as part of the immune system. Some aquatic animals have a second eyelid in each eye which refracts the light and helps them see clearly both above water and below it. Most creatures will automatically react to a threat to its eyes (such as an object moving straight at the eye, or a bright light) by covering the eyes, and/or by turning the eyes away from the threat. Blinking the eyes is, of course, also a reflex.
Eyelashes
In many animals, including humans, eyelashes prevent fine particles from entering the eye. Fine particles can be bacteria, but also simple dust which can cause irritation of the eye, and lead to tears and subsequent blurred vision.
Eye movement
Animals with compound eyes have a wide field of vision, allowing them to look in many directions. To see more, they have to move their entire head or even body. The visual system in the brain is too slow to process that information if the images are slipping across the retina at more than a few degrees per second (Westheimer and McKee, 1954). Thus, for humans to be able to see while moving, the brain must compensate for the motion of the head by turning the eyes. Another complication for vision in frontal-eyed animals is the development of a small area of the retina with a very high visual acuity. This area is called the fovea, and covers about 2 degrees of visual angle in people. To get a clear view of the world, the brain must turn the eyes so that the image of the object of regard falls on the fovea. Eye movements are thus very important for visual perception, and any failure to make them correctly can lead to serious visual disabilities. To see a quick demonstration of this fact, try the following experiment: hold your hand up, about one foot (30 cm) in front of your nose. Keep your head still, and shake your hand from side to side, slowly at first, and then faster and faster. At first you will be able to see your fingers quite clearly. But as the frequency of shaking passes about one hertz, the fingers will become a blur. Now, keep your hand still, and shake your head (up and down or left and right). No matter how fast you shake your head, the image of your fingers remains clear. This demonstrates that the brain can move the eyes opposite to head motion much better than it can follow, or pursue, a hand movement. When your pursuit system fails to keep up with the moving hand, images slip on the retina and you see a blurred hand. Having two eyes is an added complication, because the brain must point both of them accurately enough that the object of regard falls on corresponding points of the two retinas; otherwise, double vison would occur. The movements of different body parts are controlled by striated muscles acting around joints. The movements of the eye are no exception, but they have special advantages not shared by skeletal muscles and joints, and so are considerably different.
Extraocular muscles
Each eye has six muscles that control its movements: the lateral rectus, the medial rectus, the inferior rectus, the superior rectus, the inferior oblique, and the superior oblique. When the muscles exert different tensions, a torque is exerted on the globe that causes it to turn. This is an almost pure rotation, with only about one millimeter of translation (Carpenter, 1988). Thus, the eye can be considered as undergoing rotations about a single joint in the center of the eye.
Rapid eye movement
Rapid eye movement typically refers to the stage during sleep during which the most vivid dreams occur. During this stage, the eyes move rapidly. It is not in itself a unique form of eye movement.
Saccades
Saccades are rapid refocussing actions of the eyes. Many animals are able to quickly look at a point in space (prompted by memory, peripheral vision or an audio cue) without actively looking at anything in between. The eyes simply jerk into a new position. Saccades move the eye at up to 900°/s in adult humans.
Microsaccades
Even when looking intently at a single spot, the eyes drift around. This ensures that individual photosensitive cells are continually stimulated in different degrees. Without changing input, these cells would otherwise stop generating output. Microsaccades move the eye no more than a total of 0.2° in adult humans.
Vestibulo-ocular reflex
Many animals can look at something while turning their heads. The eyes are automatically rotated to remain fixed on the object, directed by input from the organs of balance near the ears.
Smooth pursuit movement
The eyes can also follow a moving object around. This is less accurate than the vestibulo-ocular reflex as it requires the brain to process incoming visual information and supply feedback. Following an object moving at constant speed is relatively easy, though the eyes will often make saccadic jerks to keep up. The smooth pursuit movement can move the eye at up to 100°/s in adult humans.
Optokinetic reflex
The optokinetic reflex is a combination of a saccade and smooth pursuit movement. When, for example, looking out of the window in a moving train, the eyes can focus on a 'moving' tree for a short moment (through smooth pursuit), until the tree moves out of the field of vision. At this point, the optokinetic reflex kicks in, and moves the eye back to the point where it first saw the tree (through a saccade).
Vergence movement
feedback When a creature with binocular vision looks at an object, the eyes must rotate around a vertical axis so that the projection of the image is in the centre of the retina in both eyes. To look at an object closer by, the eyes rotate 'towards each other' (convergence), while for an object farther away they rotate 'away from eachother' (divergence). Exaggerated convergence is called cross eyed viewing (focussing on the nose for example) . When looking into the distance, or when 'staring into nothingness', the eyes neither converge nor diverge. Vergence movements are closely connected to accommodation of the eye. Under normal conditions, changing the focus of the eyes to look at an object at a different distance will automatically cause vergence and accommodation.
Accommodation
To see clearly, the lens will be pulled flatter or allowed to regain its thicker form.
Diseases, disorders, and age-related changes
There are many diseases and disorders that may affect the eyes. As the eye ages certain changes occur that can be attributed to solely the aging process. Most of these anatomic and physiologic processes follow a gradual decline. With aging, the quality of vision worsens due to reasons independent of aging eye diseases. While there are many changes of significance in the nondiseased eye, the most functionally important changes seem to be a reduction in pupil size and the loss of accommodation or focusing capability (presbyopia). The area of the pupil governs the amount of light that can reach the retina. The extent to which the pupil dilates also decreases with age. Because of the smaller pupil size, older eyes receive much less light at the retina. In comparison to younger people, it is as though older persons wear medium-density sunglasses in bright light and extremely dark glasses in dim light. Therefore, for any detailed visually guided tasks on which performance varies with illumination, older person requires extra lighting. With aging a prominent white ring develops in the periphery of the cornea- called arcus senilis. Aging causes laxity and downward shift of eyelid tissues and atrophy of the orbital fat. These changes contribute to the etiology of several eyelid disorders such as ectropion, entropion, dermatochalasis,and ptosis. The vitreous gel undergoes liquefaction (posterior vitreous detachment or PVD) and its opacities - visible as floaters gradually increase in number.
See also

- WikiSaurus:eye — the WikiSaurus list of synonyms and slang words for eyes in many languages
- Adaptation
- Binocular vision
- Corrective lens
- Crystallin
- Evil eye
- Eye color
- Eye contact
- Eye tracking
- Eyeglass prescription
- Macropsia
- Micropsia
- Nictitating membrane
- Ocular tremor
- Ophthalmology
- Optician
- Optometry
- Persistence of vision
- Phosphenes
- Snellen chart
- Staring contest
- Tears
- Visual perception
External links

- [http://www.djo.harvard.edu/ DJO | Digital Journal of Ophthalmology]
- [http://www.afb.org/eyeconditions.asp Glossary of Eye Conditions]
- [http://www.pbs.org/wgbh/evolution/library/01/1/l_011_01.html Evolution of the Eye]
- [http://www.eyetopics.com eye Topics]
- [http://webvision.med.utah.edu/anatomy.html Diagram of the eye]
- [http://webvision.med.utah.edu/ Webvision. The organisation of the retina and visual system.]
References

-
-
- [http://soma.npa.uiuc.edu/courses/bio303/Ch11b.html Internet lecture on eye types in animal kindom] # [http://www.agingeye.net/ AgingEye Times] Category:Visual system Category:Head and neck Category:Ophthalmology ms:Mata ja:目 zh-min-nan:Ba̍k-chiu

1897

1897 was a common year starting on Friday (see link for calendar).

Events

common year starting on Friday
- January 1 - Brooklyn, New York merges with New York City.
- January 4 - A British force is ambushed by Chief Ologbosere, son-in-law of the Oba of Benin. This leads to a Punitive Expedition against Benin.
- February 2 - Harrisburg, the Pennsylvania state capitol, is destroyed by fire.
- February 18- Benin is put to the torch by the Punitive Expedition.
- March 4 - William McKinley succeeds Grover Cleveland as President of the United States.
- March 13 - San Diego State University founded.
- April 5 - "Ordinance of April 5," equalizing German and Czech in Bohemia, signed in Austria-Hungary (see Kasimir Felix Graf Badeni).
- April 27 - Grant's Tomb is dedicated.
- May 19 - Oscar Wilde is released from prison.
- June 2 - Mark Twain, responding to rumors that he was dead, is quoted by the New York Journal as saying, "The report of my death was an exaggeration."
- July 17 - Klondike Gold Rush begins when first successful prospectors arrive in Seattle.
- July 25 - Writer Jack London sails to join the Klondike Gold Rush where he will write his first successful stories.
- July 31 - First ascent of Mount Saint Elias, second highest peak in the United States and Canada.
- August 29 - First Zionist Congress convenes in Basel, Switzerland.
- September 1 - The Boston subway opens, becoming the first underground metro in North America.
- September 10 - In the Lattimer Massacre, a sheriff's posse killes more than nineteen unarmed immigrant miners in Pennsylvania.
- September 11 - After months of searching, generals of Menelik II of Ethiopia capture Gaki Sherocho, the last king of Kaffa, bringing an end to that ancient kingdom.
- December 9 - First issue of the feminist newspaper La Fronde is published by Marguerite Durand.
- December 28 - The play Cyrano de Bergerac, by Edmond Rostand, premieres in Paris.
- December 30 - Natal annexes Zululand.
- Queen Victoria celebrates her Diamond Jubilee.
- France allows women to study at the Ecole des Beaux-Arts.
- First use of the word computer meaning an electronic calculation device.
- Coseley Urban District Council formed
- Dos Equis first brewed in anticipation of new century

Births

January-March

- January 3 - Marion Davies, American actress (d. 1961)
- January 23 - Margarete Schütte-Lihotzky, Austrian architect and anti-Nazi activist (d. 2000)
- February 4 - Ludwig Erhard, Chancellor of Germany (d. 1977)
- February 7 - Quincy Porter, American composer (d. 1966)
- February 10 - John F. Enders, American scientist, recipient of the Nobel Prize in Physiology or Medicine (d. 1985)
- February 10 - Dame Judith Anderson, Australian actress (d. 1992)
- February 27 - Marian Anderson, American contralto (d. 1993)
- March 1 - Shoghi Effendi, Guardian of the Bahá'í Faith (d.1957)
- March 2 - Violet Baudelaire, heiress to the Baudelaire inheritance (d.1980)
- March 4 - Lefty O'Doul, baseball player and restaurateur (d. 1969)
- March 15 - Jackson Scholz, American sprinter (d. 1986)
- March 24 - Wilhelm Reich, Austrian psychotherapist (d. 1957)
- March 28 - Sepp Herberger, German football coach (d. 1977)

April-June

- April 1 - Nita Naldi, American film actress (d. 1961)
- April 7 - Walter Winchell, American broadcast journalist (d. 1972)
- April 9 - John B. Gambling, American radio talk-show host (d. 1974)
- April 19 - Peter de Noronha, Indian businessman
- April 23 - Lester B. Pearson, Prime Minister of Canada, recipient of the Nobel Peace Prize (d. 1972)
- April 25 - Mary, Princess Royal of England (d. 1965)
- April 26 - Douglas Sirk, German-born director (d. 1987)
- April 26 - Eddie Eagan, American boxer and bobsledder (d. 1967)
- May 14 - Sidney Bechet, American musician (d. 1959)
- May 17 - Odd Hassel, Norwegian chemist, Nobel Prize laureate (d. 1981)
- May 18 - Frank Capra, American producer, director, and writer (d. 1991)
- May 19 - Frank Luke, American World War I pilot (d. 1918)
- May 21 - Nikola Avramov, Bulgarian painter (d. 1945)
- May 27 - John Cockcroft, English physicist, Nobel Prize laureate (d. 1967)
- May 29 - Erich Wolfgang Korngold, Austrian composer (d. 1957)
- June 7 - George Szell, Hungarian conductor (d. 1970)
- June 10 - Grand Duchess Tatiana of Russia (d. 1918)
- June 13 - Paavo Nurmi, Finnish runner (d. 1973)
- June 16 - Georg Wittig, German chemist, Nobel Prize laureate (d. 1987)
- June 19 - Cyril Norman Hinshelwood, English chemist, Nobel Prize laureate (d. 1967)
- June 19 - Moe Howard, American comedian and actor, Three Stooges member (d.1975)

July-September

- July 20 - Tadeus Reichstein, Polish-born chemist, recipient of the Nobel Prize in Physiology or Medicine (d. 1996)
- July 24 - Amelia Earhart, American aviator
- July 29 - Sir Neil Ritchie, British general (d. 1983)
- August 2 - Max Weber, Swiss Federal Councilor (d. 1974)
- August 28 - Charles Boyer, French actor (d. 1978)
- September 8 - Jimmie Rodgers, American singer (d. 1933)
- September 12 - Irene Joliot-Curie, French physicist, recipient of the Nobel Prize in Chemistry (d. 1956)
- September 17 - Earl Webb, baseball player (d. 1965)
- September 23 - Walter Pidgeon, Canadian actor (d. 1984)
- September 25 - William Faulkner, American writer, Nobel Prize laureate (d. 1962)
- September 26 - Pope Paul VI (d. 1978)
- September 26 - Arthur Rhys Davids, English pilot (d.1917)

October-December

- October 3 - Louis Aragon, French author (d. 1982)
- October 15 - Johannes Sikkar, Estonian statesman (d. 1960)
- October 20 - Yi, Eun, Korean Crown Prince (d. 1970)
- October 29 - Joseph Goebbels, German Nazi propagnadist (d. 1945)
- November 9 - Ronald George Wreyford Norrish, British chemist, Nobel Prize laureate (d. 1978)
- November 15 - Sacheverell Sitwell, English author (d. 1988)
- November 18 - Patrick Blackett, English physicist, Nobel Prize laureate (d. 1974)
- November 23 - Nirad C. Chaudhuri, Bengali author (d. 1999)
- December 18 - Fletcher Henderson, American musician (d. 1952)
- December 30 - Alfredo Bracchi, Italian author (d. 1976)

Deaths

- February 4 - Major Charles Bendire, U.S. Army captain and ornithologist (b. 1836)
- February 19 - Karl Weierstrass, German mathematician (b. 1815
- March 19 - Antoine Thomson d'Abbadie, Irish-born traveler (b. 1810)
- April 3 - Johannes Brahms, German composer (b. 1833)
- September 9 - Richard Holt Hutton, English writer and theologian (b. 1826)
- September 21 - Wilhelm Wattenbach, German historian (b. 1819)
- October 29 - Henry George, American economist (b. 1839)
- November 19 - William Seymour Tyler, American educator and historian (b. 1810)
- November 20 - Ernest Giles, Australian explorer (b. 1835)
- December 17 - Alphonse Daudet, French writer (b. 1840)
- Jang Seung-eop, Korean painter (b. 1843) Category:1897 ko:1897년 ms:1897 simple:1897 th:พ.ศ. 2440

May 4

May 4 is the 124th day of the year in the Gregorian calendar (125th in leap years). There are 241 days remaining.

Events

- 1471 - Wars of the Roses: The Battle of Tewkesbury – Edward IV defeats a Lancastrian Army and kills Edward, Prince of Wales.
- 1493 - Pope Alexander VI divides the New World between Spain and Portugal along the Demarcation Line.
- 1494 - Christopher Columbus lands in Jamaica.
- 1626 - Dutch explorer Peter Minuit arrives in New Netherland (present day Manhattan Island) aboard the See Meeuw.
- 1675 - King Charles II of England orders the construction of the Royal Greenwich Observatory.
- 1776 - Rhode Island becomes the first American colony to renounce allegiance to King George III.
- 1814 - Emperor Napoleon I of France arrives at Portoferraio on the island of Elba to begin his exile.
- 1855 - American adventurer William Walker departs from San Francisco with about 60 men to conquer Nicaragua.
- 1863 - American Civil War: Battle of Chancellorsville – The battle ends with a Union retreat.
- 1865 - Abraham Lincoln buried in Springfield, Illinois, three weeks after his assassination.
- 1869 - The Naval Battle of Hakodate takes place in Japan.
- 1871 - The National Association, the first professional baseball league, begins its first season.
- 1886 - Haymarket Square Riot: A bomb is thrown at policemen trying to break up a labor rally in Chicago, Illinois, United States, killing eight and wounding 60. The police fire into the crowd.
- 1904 - Construction begins by the United States on the Panama Canal.
- 1910 - The Royal Canadian Navy is created.
- 1912 - Italy occupies the island of Rhodes.
- 1919 - May Fourth Movement: Student demonstrations take place in Tiananmen Square in Beijing, China, protesting the Treaty of Versailles, which transferred Chinese territory to Japan.
- 1924 - The 1924 Summer Olympics open in Paris, France.
- 1930 - British police arrest Mahatma Gandhi and place him in Yeravda Central Prison.
- 1932 - In Atlanta, Georgia, mobster Al Capone begins serving an eleven-year prison sentence for tax evasion.
- 1942 - World War II: Battle of the Coral Sea – The battle begins with the launch of attack aircraft from American and Japanese aircraft carriers.
- 1945 - World War II: Liberation of the Neuengamme concentration camp near Hamburg by the British Army.
- 1945 - World War II: Surrender of the North Germany Army to Field Marshal Bernard Montgomery.
- 1946 - In San Francisco Bay, US Marines from the Treasure Island Marine Barracks stop a two-day riot at Alcatraz federal prison. Five people are killed in the riot.
- 1948 - Norman Mailer's first novel, The Naked and the Dead, is published.
- 1949 - The entire Torino football (soccer) team (except for one player who did not take the trip due to an injury) is killed in a plane crash at the Superga hill at the edge of Turin, Italy.
- 1953 - Ernest Hemingway is awarded the Pulitzer Prize for The Old Man and the Sea.
- 1959 - The first Grammy Awards are announced.
- 1961 - American civil rights movement: The "Freedom Riders" begin a bus trip through the South.
- 1970 - Vietnam War: Kent State shootings – The Ohio National Guard, sent to Kent State University after the ROTC building was burnt down, opens fire on students protesting at the United States' invasion of Cambodia. Four students are killed, nine are wounded.
- 1972 - The Don't Make A Wave Committee, a fledgling environmental organization founded in Canada in 1971, officially changed its name to "Greenpeace Foundation".
- 1974 - An all-female Japanese team reaches the summit of Manaslu, becoming the first women to climb an 8,000-meter peak.
- 1979 - Margaret Thatcher becomes the first woman Prime Minister of the United Kingdom.
- 1980 - President Josip Broz Tito of Yugoslavia dies in Ljubljana at the age of 87.
- 1989 - Iran-Contra Affair: Former White House aide Oliver North is convicted of three crimes and was acquitted of nine other charges. The convictions, however, are later overturned on appeal.
- 1990 - Latvia proclaims independence.
- 1990 - Robert Murray, Handsome American Jokester, Inventor, Actor, Athlete, Scientist, Chemist, Screamer, DJ, Burger King, Top 10 Guy on www.facebattle.com, and Decorated War Hero is born. The world celebrates, and endangered species are repopulated.
- 1991 - In Rome, Italy, Carola wins the thirty-sixth Eurovision Song Contest for Sweden singing "Fångad av en stormvind" (Trapped in a storm wind).
- 1994 - Israeli Prime Minister Yitzhak Rabin and PLO leader Yasser Arafat sign a peace accord regarding Palestinian autonomy granting self-rule in the Gaza Strip and Jericho.
- 1996 - José María Aznar is appointed Prime Minister of Spain, thus ending 13 years of Socialist rule.
- 1998 - A federal judge in Sacramento, California, gives "Unabomber" Theodore Kaczynski four life sentences plus 30 years after Kaczynski accepted a plea agreement sparing him from the death penalty.
- 1999 - In California, Manuel Babbitt is executed for the 1980 murder of Leah Schendel. While on death row Babbitt was awarded a Purple Heart for injuries he received in the Vietnam War.
- 2002 - An EAS Airlines BAC 1-11-500 crashes in a suburb of Kano, Nigeria shortly after takeoff killing more than 148 people.
- 2003 - The Outbreak of 2003 begins. Ninety-four tornadoes begin the week-long outbreak.

Births

- 1008 - King Henry I of France (d. 1060)
- 1654 - Kangxi Emperor of China (d. 1722)
- 1655 - Bartolomeo Cristofori, Italian maker of musical instruments (d. 1731)
- 1715 - Richard Graves, English writer (d. 1804)
- 1733 - Jean-Charles de Borda, French mathematician, physicist, political scientist, and sailor (d. 1799)
- 1772 - Friedrich Arnold Brockhaus, German publisher (d. 1823)
- 1781 - Karl Christian Friedrich Krause, German philosopher (d. 1832)
- 1796 - Horace Mann, American educator (d. 1859)
- 1820 - Julia Tyler, First Lady of the United States (d. 1889)
- 1825 - Thomas Henry Huxley, English scientist (d. 1895)
- 1825 - Augustus Le Plongeon, French archaeologist (d. 1908)
- 1826 - Frederic Edwin Church, American painter (d. 1900)
- 1827 - John Hanning Speke, British explorer (d. 1864)
- 1852 - Alice Pleasance Liddell, English schoolgirl model for Alice in Wonderland (d. 1934)
- 1870 - Alexandre Benois, Russian artist (d. 1860)
- 1873 - Joe De Grasse, Canadian film director (d. 1940)
- 1889 - Francis Cardinal Spellman, American religious leader (d. 1967)
- 1903 - Luther Adler, American stage actor (d. 1984)
- 1918 - Tanaka Kakuei, Japanese political leader (d. 1993)
- 1921 - Edo Murtić, Croatian painter (d. 2005)
- 1923 - Eric Sykes, British actor and comedian
- 1928 - Maynard Ferguson, Canadian musician
- 1928 - Hosni Mubarak, President of Egypt
- 1929 - Audrey Hepburn, Belgian actress (d. 1993)
- 1929 - Sidney Lamb, American linguist
- 1930 - Roberta Peters, American soprano
- 1931 - Gennady Rozhdestvensky, Russian composer
- 1936 - El Cordobes, Spanish bullfighter
- 1937 - Dick Dale, American guitarist
- 1939 - Amos Oz, Israeli writer, novelist, and journalist
- 1941 - George Will, American writer
- 1942 - Nickolas Ashford, American record producer, songwriter, musician (Ashford and Simpson)
- 1942 - Tammy Wynette, American musician (d. 1998)
- 1944 - Roger Rees, British-born actor
- 1945 - Narasinham Ram, Indian journalist
- 1949 - John Force, American race car driver
- 1954 - Pia Zadora, American actress
- 1956 - David Guterson, American author
- 1956 - Ulrike Meyfarth, German athlete
- 1958 - Keith Haring, American graphical artist (d. 1990)
- 1959 - Randy Travis, American musician
- 1962 - Oleta Adams, American singer
- 1967 - Ana Gasteyer, American actress
- 1972 - Mike Dirnt, American musician (Green Day)
- 1976 - Jason Michaels, baseball player
- 1979 - Lance Bass, American musician (
- NSYNC)
- 1981 - Eric Djemba-Djemba, Cameroon footballer
- 1984 - Markus Rogan, Austrian swimmer
- 1985 - Anthony Fedorov, American singer
- 1987 - Rebecca Wagoner, American college student
- 1989 - Becca Evans, Alcoholic rocker
- 1994 - Alexander Gould, American actor

Deaths

- 1471 - Edward of Westminster, Prince of Wales (killed in battle) (b. 1453)
- 1471 - Edmund Beaufort, 4th Duke of Somerset, English military commander (executed)
- 1506 - Husayn Bayqarah, ruler of Herat (b. 1438)
- 1519 - Lorenzo II de' Medici, Duke of Urbino (b. 1492)
- 1566 - Luca Ghini, Italian physician and botanist (b. 1490)
- 1615 - Adriaan van Roomen, Flemish mathematician (b. 1561)
- 1626 - Arthur Lake, Bishop of Bath and Wells, English bishop and Bible translator (b. 1569)
- 1677 - Is