title: William Howard Taft

text: In 1921, Taft was appointed by Warren Harding to be the 10th Chief Justice of the United States Supreme Court, making Taft the only former president to become Chief Justice. He retired from the job on February 3, 1930 due to bad health.


title: William Howard Taft

text: Taft was the most obese president. He was tall and his weight was between and toward the end of his presidency. He had difficulty getting out of the White House bathtub, so he had a long, wide tub installed. This tub could accommodate four normal-sized people. It was replaced in 1951 with a modern tub of similar size.


title: William Howard Taft

text: Taft died on March 8, 1930 due to heart failure. Three days later, he became the first president to be buried at Arlington National Cemetery.


title: Camel toe

text: Camel toe, or cameltoe, is slang for when the outline of a woman's labia majora is seen in tightly fitting clothes. The male equivalent of cameltoe is "mooseknuckle". It is called a "camel toe" because of how the woman's labia outline is similar to that of a camel's toe.


title: Camel toe

text: Camel toe happens as a result of wearing tight-fitting clothes, such as shorts, leggings or swimwear.


title: Bird

text: Birds (Aves) are a group of animals with backbones which evolved from dinosaurs. Technically speaking, they are dinosaurs.


title: Bird

text: Modern birds are toothless: they have beaked jaws. They lay hard-shelled eggs. They have a high metabolic rate, a four-chambered heart and a strong yet lightweight skeleton.


title: Bird

text: Birds live all over the world. They range in size from the 5 cm (2 in) bee hummingbird to the 2.70 m (9 ft) ostrich. They are the tetrapods with the most living species: about ten thousand. More than half of these are passerines, sometimes known as perching birds.


title: Bird

text: Birds are the closest living relatives of the Crocodilia. This is because they are the two main survivors of a once huge group called the Archosaurs.


title: Bird

text: Modern birds are "not" descended from "Archaeopteryx". According to DNA evidence, "modern" birds (Neornithes) evolved in the long Upper Cretaceous period. More recent estimates showed that modern birds originated early in the Upper Cretaceous.


title: Bird

text: Primitive bird-like dinosaurs are in the broader group Avialae. They have been found back to the mid-Jurassic period, around 170 million years ago. Many of these early "stem-birds", such as "Anchiornis", were not yet capable of fully powered flight. Many had primitive characteristics like teeth in their jaws and long bony tails.


title: Bird

text: The Cretaceous–Palaeogene extinction event 66 million years ago killed off all the non-avian dinosaur lines. Birds, especially those in the southern continents, survived this event and then migrated to other parts of the world. Diversification occurred around the Cretaceous–Palaeogene extinction event.


title: Bird

text: Birds have wings which are more or less developed depending on the species. The only known groups without wings are the extinct moa and elephant birds. Wings, which evolved from forelimbs, gave birds the ability to fly. Later, many groups evolved with reduced wings, such as ratites, penguins and many island species of birds. The digestive and respiratory systems of birds are also adapted for flight. Some bird species in aquatic environments, particularly seabirds and some waterbirds, have evolved as good swimmers.


title: Bird

text: In general, birds are effective, and inherit their behaviour almost entirely. The key elements of their life are inherited. It was a great discovery that birds never learn to fly.


title: Bird

text: So it is quite wrong to say, when a chick waves its wings in the nest "It's learning to fly". What the chick is doing is exercising its muscles. They develop the ability to fly "automatically" (assuming they are species that do fly). And if they are species which migrate, that behaviour is also inherited. Many species migrate over great distances each year. Other main features of their life may be inherited, though they can and do learn. Birds have good memories which they use, for example, when they search for food.


title: Bird

text: Several bird species make and use tools. Some social species pass on some knowledge across generations, a form of culture. Birds are social. They communicate with visual signals, calls and bird songs. Most of their social behaviours are inherited, such as cooperative breeding and hunting, flocking and mobbing of predators.


title: Bird

text: Most bird species are socially monogamous, usually for one breeding season at a time, sometimes for years, but rarely for life. Other species are polygynous (one male with many females) or, rarely, polyandrous (one female with many males). Birds produce offspring by laying eggs which are fertilised by sexual reproduction. They are often laid in a nest and incubated by the parents. Most birds have an extended period of parental care after hatching. Some birds, such as hens, lay eggs even when not fertilised, though unfertilised eggs do not produce offspring.


title: Bird

text: Many species of birds are eaten by humans. Domesticated and undomesticated birds are sources of eggs, meat, and feathers. In English, domesticated birds are often called poultry, undomesticated birds are called game. Songbirds, parrots and other species are popular as pets. Guano, which is bird manure, is harvested for use as a fertiliser. Birds figure throughout human culture. About 120–130 species have become extinct due to human activity since the 17th century and hundreds more before then. Human activity threatens about 1,200 bird species with extinction, though efforts are underway to protect them. Recreational bird-watching is an important part of the ecotourism industry.


title: Bird

text: Birds come in a huge range of colours. These colours can be useful to a bird in two ways. Camouflage colours help to hide the bird, and bright colours identify the bird to others of the same species. Often the male is brightly coloured while the female is camouflaged. The logic is as follows: the female carries the "precious package" of developing eggs. The male has to defend a territory, and the function of his colour and song is to let others know that "this place is occupied".


title: Bird

text: Many birds are brown, green or grey. These colours make a bird harder to be seen: they camouflage the bird. Brown is the most common colour. Brown birds include: sparrows, emus, thrushes, larks, eagles and falcons and the female birds of many species such as: wrens, ducks, blackbirds and peafowls. When a brown bird is in long grass or among tree trunks or rocks, it is "camouflaged". Birds that live in long grass often have brown feathers streaked with black which looks like shadows. A bittern is almost invisible in long reeds because its camouflage is helped by its posture (beak and head pointed upwards). Other birds, including starlings and mynas, are quite dark in colour, but are flecked with little spots that look like raindrops on leaves. Bird may also camouflage their nests.


title: Bird

text: Many birds from hot countries are green or have some green feathers, particularly parrots. Birds that live in green trees often have green backs, even if they have bright-coloured breasts. From the back, the birds are camouflaged. This is very useful when sitting on a nest. The bird's bright-coloured breast is hidden. Budgerigars are bred in different colours such as blue, white and mauve, but in the wild, they are nearly all green and yellow. Even though they fly very well, they normally spend a lot of time on the ground, eating grass seeds. Their yellow and black striped back helps to hide them in the shadows made by long dry grass, while their green breasts are a similar colour to the leaves of gum trees.


title: Bird

text: Grey birds include most pigeons and doves, cranes, storks and herons. Grey birds are often rock-living birds like pigeons or birds that sit on dead tree trunks looking like a broken branch. Water birds like herons often have a pale grey colour which makes it harder for a fish to notice that the bird is standing, looking down for something to catch. Water birds, no matter what colour they are on top, are often white underneath, so that when a fish looks up, the bird looks like part of the sky.


title: Bird

text: Black birds include crows, ravens and male blackbirds. Some birds that are dark colours spend quite a lot of time on the ground, hopping around in the shadows under bushes. Among these birds are the male blackbird and the satin bowerbird which is not black but very dark blue. Crows and ravens often perch high on bare trees in the winter, where their black shape against the sky looks like the dark bare branches.


title: Bird

text: Many birds are not camouflaged, but stand out with vivid colours. They are usually male birds whose females are dull and camouflaged. The function of the colours is two-fold. First, the colours help them get mates, and second, the colours identify them to other males of the same species. Many birds are territorial, especially in the nesting season. They give out territory sounds and are easily seen. This lets other males know they will defend their territory. It sends out a "look elsewhere" signal to their competitors.


title: Bird

text: Some birds are famous for their colour and some are named for it, such as the bluebird, the azure kingfisher, the golden pheasant, the scarlet macaw. The European robin is known popularly as the red robin.


title: Bird

text: Many other birds are very brightly coloured, in countless combinations. Some of the most colourful birds are quite common, like pheasants, peacocks, domestic fowl and parrots. Colourful small birds include blue tits, the goldfinches, hummingbirds, fairy wrens and bee eaters (which are also called rainbow birds). Some birds, like those of the bird of paradise in Papua New Guinea have such beautiful feathers that they have been hunted for them.


title: Bird

text: The peafowl is the best example of a display of colour to attract a mate. Also the male domestic fowl and junglefowl have long shiny feathers above his tail and also long neck feathers that may be a different colour to his wings and body. There are only a few species of birds (such as the eclectus parrot) where the female is more colourful than the male.


title: Bird

text: <nowiki>"Pied birds"</nowiki> are black and white. Black and white birds include magpies, pied geese, pelicans and Australian magpies (which are not really magpies at all). Pied birds often have brightly coloured beaks and legs of yellow or red. The silver pheasant, with its long white tail striped with fine bars of black, has a brightly coloured face.


title: Bird

text: Most birds can fly, and if they do, then the ability is inherited, not learnt. They fly by pushing through the air with their wings. The curved surfaces of the wings cause air currents (wind) which lift the bird. Flapping keeps the air current moving to create lift and also moves the bird forward.


title: Bird

text: Some birds can glide on air currents without flapping. Many birds use this method when they are about to land. Some birds can also hover in the air. This method is used by birds of prey such as falcons that are looking for something to eat. Seagulls are also good at hovering, particularly if there is a strong breeze. The most expert hovering birds are tiny hummingbirds which can beat their wings both backwards and forwards and can stay quite still in the air while they dip their long beaks into flowers to feed on the sweet nectar.


title: Bird

text: Different types of birds have different needs. Their wings have evolved to suit their lifestyle. Large birds of prey, such as eagles, spend a lot of time soaring on the wind. They have wings that are large and broad. The main flight feathers are long and wide. They help the eagle to stay on rising air currents without using much energy, while the eagle looks at the ground below, to find the next meal. When the eagle sees some small creature move, it can close its wings and fall from the sky like a missile, opening its great wings again to slow down as it comes to land. The world's largest eagle, the Philippine eagle has a wingspan of about 2 m (6.7 ft) wide.


title: Bird

text: Birds that live in grassland areas or open forests and feed on fruit, insects and reptiles often spend a lot of time flying short journeys looking for food and water. They have wings that are shaped in a similar way to eagles, but rounder and not as good for soaring. These include many Australian birds like cockatoos.


title: Bird

text: Birds such as geese that migrate from one country to another fly very long distances. Their wings are big and strong, because the birds are large. They stock up on food for the long flight. Migrating water birds usually form family groups of 1230 birds. They fly very high, making use of long streams of air that blow from north to south in different seasons. They are well organised, often flying in a V pattern. The geese at the back do not have to flap so hard; they are pulled on by the wind of the ones at the front. Every so often, they change the leader so that the front bird, who does most work and sets the pace, can have a rest. Geese and swans are the highest-flying birds, reaching 8,000 metres or more when on migration. Geese often "honk" loudly while they are flying. It is thought that they do this to support the leader and help the young ones.


title: Bird

text: Birds that fly very quickly, such as swifts and swallows, have long narrow pointed wings. These birds need great speed because they eat insects, catching most of them while they are flying. These birds also migrate. They often collect in huge flocks of thousands of birds that move together like a whirling cloud.


title: Bird

text: Birds that live in bushes and branches have triangular wings that help the bird change direction. Many forest birds are expert at getting up speed by flapping and then gliding steadily among the trees, tilting to avoid things as they go.


title: Bird

text: Birds such as owls that hunt at night have wings with soft rounded feathers so that they do not flap loudly. Birds that are awake at night are called "nocturnal" birds. Birds that are awake during the day are "diurnal".


title: Bird

text: Wandering albatross might spend several years without coming to land. They can sleep while gliding. Arctic terns nest every one to three years.


title: Bird

text: Flocks of birds can be very highly organised in a way that takes care of all the flock members. Studies of small flocking birds like tree sparrows show that they clearly communicate with each other, as sometimes thousands of birds may fly in close formation and spiral patterns without colliding (or flying into each other).


title: Bird

text: Two common behaviours in flocking birds are guarding and reconnaissance. When a flock of birds is feeding it is common for one bird to perch on a high place to keep guard over the flock. In the same way, when a flock is asleep, often, one bird will remain awake. It is also common for large flocks to send one or two birds ahead of them when they are flying to a new area. The look-out birds can spy the lie of the land to find food, water and good places to perch. Mixed feeding flocks occur, and can help to spot predators.


title: Bird

text: These include running birds like ostriches and emus and ocean-living birds, the large penguin family. Birds on islands have usually lost the power of flight. This is to their advantage because birds with the power of flight can be blown off their island during a storm. The same ability which got them to the island may later take them away in a storm.


title: Bird

text: Ostriches and emus do not need to fly because although they feed and nest on the ground, their great size and their speed is their protection. Some other ground-feeding birds have not been so lucky. Some birds such as the dodo and the kiwi were ground-feeding birds that lived in safety on islands where there was nothing dangerous to eat them. They lost the power of flight. Kiwis are endangered because European settlement to New Zealand brought animals like cats, dogs and rats which kill kiwis and eat their eggs. However, kiwis and also the rare New Zealand ground parrot have survived. In the case of dodos, they were fat and disgusting in taste. All the same, they were killed and eaten by sailors until there was none left. Other flightless birds which have disappeared are the great auk and the moa.


title: Bird

text: Penguins are a very successful group of birds. They are a clade. They spend half their time on land. Their wings are adapted to life in the sea and have become flippers which let them in swim fast. They catch fish at sea, where they are in danger from seals.


title: Bird

text: Preening is how birds keeps their feathers in order. They use their beak to position feathers, interlock feather barbules that have become separated, clean plumage, and keep ectoparasites in check.


title: Bird

text: Feathers in good shape help the bird's insulation, waterproofing and flight. Their condition is vital to the bid's survival.


title: Bird

text: Modern birds do not have teeth, and many swallow their prey whole. Nevertheless, they must break up food before it is digested. First of all, along their throat (oesophagus) they have a crop. This stores food items before digestion. That way a bird can eat several items, and then fly off to a quiet spot to digest them.


title: Bird

text: Their stomach comes next, with two very different parts. One part is like a straight hollow rod (the "proventriculus") which secretes mild hydrochloric acid and an enzyme to break down protein. The other part of the stomach is the gizzard. This is muscular, and grinds up the contents. In herbivorous birds the gizzard contains some gastroliths (small stones or pieces of grit). Bones of fish will mostly be dissolved by the stomach acid. The partly digested and ground-up food now goes to the intestine, where digestion is completed, and most contents are absorbed. Anything indigestible, for example remains of feathers, is regurgitated via the mouth, not the cloaca.


title: Bird

text: The system is effective, and carnivorous birds can swallow quite large prey. A blue heron can swallow a fish as large as a carp successfully. Raptors eat by holding the prey down with a foot, and tearing it apart with their beak.


title: Bird

text: Although birds are warm-blooded creatures like mammals, they do not give birth to live young. They lay eggs as reptiles do, but the shell of a bird's egg is hard. The baby bird grows inside the egg, and after a few weeks hatches (breaks out of the egg).


title: Bird

text: Birds in cold climates usually have a breeding season once a year in the spring. Migratory birds can have two springs and two mating seasons in a year.


title: Bird

text: Ninety-five per cent of bird species are socially monogamous. These birds pair for at least the length of the breeding season. In some cases this arrangement lasts until the death of one of the pair. Monogamy clearly helps if females need males' help to raise a brood successfully. It has other practical advantages: the nest is never left without defence. Birds are generally small, and they have many potential enemies.


title: Bird

text: Some birds mate for life, like married couples. These birds include pigeons, geese, and cranes. Other birds look for new partners each year. For birds that choose new mates, part of the breeding season is display. The male bird will do all sorts of things to attract females. These include singing, dancing, showing off the feathers and building a beautiful nest. Some male birds have splendid feathers for attracting females. The most famous is the peacock who can spread the feathers above his tail into a huge fan.


title: Bird

text: Other mating systems do occur in some species. Polygyny, polyandry, polygamy, polygynandry, and promiscuity do happen. Polygamous breeding systems arise when females are able to raise broods without the help of males. Some species may use more than one system depending on the circumstances.


title: Bird

text: Once the birds have found partners, they find a suitable place to lay eggs. The idea of what is a suitable place differs between species, but most build bird nests. The bird is driven by a hormone (estradiol E2) to prepare a place for the eggs to hatch. Birds' nests may be up a tree, in a cliff or on the ground according to species. When filled with eggs they are almost always guarded by one of the pair. In fact it is virtually impossible for the eggs to survive if one of the parents dies.


title: Bird

text: Robins will make a beautiful little round nest of woven grass and carefully line it with feathers, bits of fluff and other soft things. Swallows like to nest near other swallows. They make nests from little blobs of clay, often on a beam near the roof of a building where it is well sheltered. Many birds like a hollow tree to nest in. Eagle's nests are often just piles of dead wood on the top of the tallest tree or mountain. Scrub turkeys scratch together a huge pile of leaves that may be 10 metres across. Guillemots lay their eggs on rock shelves with no nest at all. Their eggs are shaped so that they roll around in circles and do not fall off cliffs. A cuckoo does not make its own nest. It lays its egg in the nest of another bird and leaves it for them to care for. The cuckoo eggs are camouflaged to look like the host's eggs.


title: Bird

text: When the nest has been prepared, the birds mate so that the eggs are fertilised and the chicks will start growing. Unlike mammals, birds (and reptiles) only have one opening as the exit hole for body fluids, and for reproduction. The opening is called the cloaca. A female bird, called a hen, has two ovaries, of which the left one usually produces eggs.


title: Bird

text: Most male birds have no sex organs that can be seen. But inside the male are two testes which produce sperm which is stored in the cloaca. Birds mate by rubbing their cloacas together, although with some birds, particularly large water birds, the male has a sort of a penis inside the cloaca.


title: Bird

text: Once the hen has mated, she produces fertile eggs which have chicks growing inside them. She lays the eggs in the nest. There might be just one egg or a number of them, called a clutch. Emus might lay as many as fifteen huge dark green eggs in a clutch. After the eggs are laid, they are incubated, or kept warm so the chicks form inside. Most birds stay together for the whole nesting season, and one advantage is that the work is shared. Many birds take turns sitting on the eggs, so that each adult can feed.


title: Bird

text: This is not always the case. With emus, the male does all the sitting and all the baby-minding. With emperor penguins it is also the male that cares for the egg. There is only one egg, which he keeps on his feet and under his feathers, standing in a big group of males without feeding until the chick is hatched. While the eggs are hatching, the females are at sea, catching fish, so that they can feed the chicks when they return.


title: Bird

text: Some birds put the eggs inside or on top of the mound of leaves and twigs. The mound acts like a compost heap. The decomposition of the rotting leaves causes the temperature to rise. This is heat released by the chemical action of bacterial and fungal respiration. It is the same reaction as that which keeps mammals and birds at a high temperature. The parents leave the mound. When the chicks hatch, they are able to feed themselves.


title: Bird

text: Many small birds take 2–4 weeks to hatch eggs. Albatrosses take 80 days. During this time the female loses a lot of her body weight.


title: Bird

text: The quickest hatching time is for the cuckoo. Some types of cuckoos take only 10 days. This means that when they hatch in the nest of their <nowiki>"foster parents"</nowiki>, the eggs that the parents have laid are not yet ready. Newborn cuckoos are naked, blind and ugly, but they are strong. They get under any eggs that are in the nest and throw them out before they hatch. That means that the cuckoo has the whole care of both parents. Baby cuckoos grow fast and often get bigger than the parents who feed them.


title: Bird

text: When baby birds hatch, in most types of birds, they are fed by both parents, and sometimes by older aunts as well. Their mouths are open all the time and are often very brightly coloured, which acts as a "releaser", a trigger which stimulates the parent to feed them. For birds that eat grain and fruit, the parents eat and partly digest the food for the babies. It is then vomited carefully into the baby's mouth.


title: Bird

text: Many birds, particularly those that mate for life, are very sociable and keep together in a family group which might be anything from 4 or 6 adult birds and their young to a very large flock.


title: Bird

text: As chicks grow they change the fluffy down that covers them as babies for real feathers. At this stage they are called fledglings. Other family members may help care for fledgling chicks, feeding them and protecting them from attack while parents are feeding. When the fledglings have their new feathers, they come out of the nest to learn to fly. In some types of birds, like pigeons, the parents watch over this and as the young ones get stronger, will give them flying lessons, teaching them how to glide, how to fly in spirals and how to land like an expert.


title: Bird

text: Most birds are social animals, at least part of the time. They communicate to each other using sounds and displays.


title: Bird

text: Almost all birds make sounds to communicate. The types of noises that vary greatly. Some birds can sing, and they are called songbirds or passerines. Examples are robins, larks, canaries, thrushes, nightingales. Corvids are passerines, but they do not sing. Birds that are not songbirds include: pigeons, seagulls, eagles, owls and ducks. Parrots are not songbirds, even though they can be taught to sing human songs.


title: Bird

text: All birds make noises (<nowiki>"bird vocalisation"</nowiki>), but not all sing. Songbirds are passerines, many of which have beautiful melodic songs. Songs have different functions. Danger cries are different from territorial songs and mating calls are a third type. Fledgling may also have different calls from adults. Recognition calls for partners are quite common.


title: Bird

text: The same species of bird will sing different songs in different regions. A good example of this is the currawong. This is an Australia bird which is like a black and white crow. In the autumn, families get together in large flocks and do a lot of singing. Currawongs from some areas sing much more complex songs than others. Generally, currawongs from the Blue Mountains are the finest singers. The song of the currawong can be sung as a solo, but is often performed as a choir. One bird will take the lead and sing "Warble-warble-warble-warble!" All the other birds will join in and sing "Wooooooo!". When all the birds know the song, the choir will sing the "Warble" part and the soloist will sing the "Woo!". The song changes from year to year and from place to place.


title: Bird

text: The Austrian naturalist Konrad Lorenz studied the way in which birds communicate, or talk to each other. He found that each type of bird had a number of sounds which they made automatically, when ever they felt a certain way. Every sound had an action that went with it. So, if the bird was frightened, it acted frightened and made a frightened sound. This told the other birds around it that something frightening was happening.


title: Bird

text: If a flock of birds were flying over a field, they would be calling "Fly! Fly!" But a hungry bird, seeing something good to eat down below might start calling "Food! Food!" If other birds were also hungry, they would make the same call until more birds were calling "Food! Food!" than "Fly! Fly!". At this point, the mind of the flock would be changed. Some of the birds would start to yell "Fly downwards! Fly downwards!" as they sank from the sky, until the whole flock was all noisily calling the same thing.


title: Bird

text: These communication sounds are often short hard sounds like: chirps, squeaks, squawks and twitters. Sometimes the calls are longer and more musical. They include the "Rookety-coo" sound of a pigeon and the "Cockadoodledoo!" of a rooster. The bird cannot change these sounds. They always make them in the same way. The bird is locked into making each sound every time a particular idea comes into its head. The connection between how they feel and how they call is innate: they are born with it. Some calls in some species are learnt. Then, it is the tendency to learn which is inherited.


title: Bird

text: Konrad Lorenz noticed that when birds sing, they often use a lot of their regular calls as part of the song. Lorenz had a flock of jackdaws which were scattered during World War II. One day, an old bird returned. For many months she sat on the chimney singing her song, but in the song she kept making the call which Lorenz knew meant "Come home! Come home!" One day, to the great surprise of Lorenz, a male bird flew from a passing flock and joined her on the chimney. Lorenz was sure that it was her long-lost "husband" who had found his way home at last.


title: Bird

text: Palaeontologists have found some exceptional places (lagerstätten) where fossils of early birds are found. The preservation is so good that on the best examples impressions of their feathers can be seen, and sometimes even the remains of meals they have eaten. From these remains we know that birds evolved from small carnivorous dinosaurs (theropods) in the Jurassic period. They radiated into a huge variety in the Lower Cretaceous. At the same time, their direct competitors, the pterosaurs, dwindled in numbers and variety, and became extinct at the end of the Mesozoic.


title: Bird

text: Birds are classified by taxonomists as 'Aves' (Avialae). Birds are the only living descendants of dinosaurs (strictly speaking, they "are" dinosaurs). Birds and Crocodilia are the only living members of the once-dominant Archosaur reptiles.


title: Bird

text: The class Aves is was defined (1990) as all the descendants of the most recent common ancestor of modern birds and "Archaeopteryx lithographica". But "Archaeopteryx" is almost certainly "not" the ancestor of modern birds. The transition to flight happened a number of times. The researchers offered four definitions. Birds can be:


title: Bird

text: "Archaeopteryx", from the Upper Jurassic some 150–145 million years ago (mya), was for a long time the earliest known bird which could fly. It is famous, because it was one of the first important fossils found after Charles Darwin published his ideas about evolution in the 19th century. By modern standards, "Archaeopteryx" could not fly very well. Other early fossil birds are, for example, "Confuciusornis", "Anchiornis huxlei" and other Paraves.


title: Bird

text: Many fossils of early birds and small dinosaurs have been discovered in the Liaoning Province of Northeast China. These include "Anchiornis huxlei", from about 160 mya. The fossils show that most small theropod dinosaurs had feathers. These deposits have preserved them so well that the impressions of their feathers can be clearly seen. This leads us to think that feathers evolved first as heat insulation and only later for flight. The origin of birds lies in these small feathered dinosaurs.


title: Bird

text: Palaeontologists now agree that birds are included in Maniraptora group of dinosaurs. This explains why we say that birds are living dinosaurs.


title: Bird

text: A leading authority says "Most living birds have fossil representatives in the Cenozoic"... "Key problems remain in understanding bird phylogeny... we seem to understand as little about the relationships among living birds as among Cretaceous birds". A useful source for modern birds is Clements J. 2007. "The Clements Checklist of Birds of the World". Cornel University Press (6th ed).


title: Bird

text: Some birds are eaten as food. Most usually it is the chicken and its eggs, but people often also eat geese, pheasants, turkeys and ducks. Other birds are sometimes eaten are: emus, ostriches, pigeons, grouse, quails, doves, woodcocks and even songbirds. Some species have died out because they have been hunted for food, for example the dodo and the passenger pigeon.


title: Bird

text: Many species have learned how to get food from people. The number of birds of these species has grown because of it. Seagulls and crows find food from garbage dumps. The feral pigeon ("Columba livia"), sparrows ("Passer domesticus" and starlings ("Sturnus vulgaris") live in large numbers in towns and cities all over the world.


title: Bird

text: Sometimes people also use working birds. For example, homing pigeons carry messages. Nowadays people sometimes race them for sport. People also use falcons for hunting, and cormorants for fishing. In the past, people in mines often used a canary to see if there were bad gas methane in the air.


title: Bird

text: People often have colorful birds such as parrots and mynahs as pets. These intelligent birds are popular because they can copy human talking. Because of this, some people trap birds and take them to other countries to sell. This is not usually allowed these days. Most pet birds are specially bred and are sold in pet shops.


title: Bird

text: People can catch some bird diseases, for example: psittacosis, salmonellosis, campylobacteriosis, Newcastle's disease, mycobacteriosis, influenza, giardiasis and cryptosporiadiosis. In 2005, there was an epidemic of bird influenza spreading through some parts of the world, often called avian flu.


title: Bird

text: Some people have birdboxes in their gardens to give birds a place to nest and bird tables where birds can get food and water in very cold or very dry weather. This lets people see some small birds close up which are normally hidden away in bushes and trees.


title: Bird

text: A report produced by BirdLife International every five years measures the population of birds worldwide. One in every eight types of birds is now "in decline".


title: Homosexuality

text: Homosexuality is a sexual orientation. A homosexual person is romantically or sexually attracted to people of their own gender. Men who are romantically or sexually attracted to other men are called gay. Women who are romantically or sexually attracted to other women can be called gay as well, but are usually called lesbians. People who are romantically or sexually attracted to men "and" women are called bisexual.


title: Homosexuality

text: Together homosexual, bisexual, and transgender people make up the LGBT community, which stands for "Lesbian, Gay, Bisexual, and Transgender". It is difficult to say how many people are homosexual. Homosexuality is known to exist in all cultures and countries.


title: Homosexuality

text: One may say that homosexuality is the term used for people that feel romantically or sexually attracted to their own sex, but other definitions also exist. When one views homosexuality as the term for people that feel romantically or sexually attracted to their own sex, more people are gay than when one might view homosexuality as only a term for people who do "have" sexual relationships with their own sex. Usually, the term is used to view all the people who are romantically or sexually attracted to their own sex, as well as those with such attractions who have not had a sexual relationship with their own sex yet. Nonetheless, the most visible form of homosexuality is the actual relationship. Most 'evidence' of homosexuality in ancient cultures comes from drawings of the men in an intimate relationship or sex, because it's the most obvious.


title: Homosexuality

text: The word "homosexual" comes from the Ancient Greek word "homo", meaning "same", and the Latin word for "gender". People in the LGBT community usually say "gay" instead of "homosexual." Some people also use the term "homophile" (from Greek ' ("homos", meaning "the same") and ' ("philein"; meaning "to love"). This term emphasizes romantic interest in the same sex, rather than sexual attraction.


title: Homosexuality

text: There are many different words to describe homosexual people. Some of these are used to insult homosexual people. However, the LGBT community sometimes uses these words to describe themselves because the word "homosexual" can sound too clinical. This is done to make the words less hurtful. Some words to describe homosexual men are "gay" and "queer". Words to describe homosexual women are "lesbian" and "dyke". "Lesbian" is used most often. "Dyke" is used less often and is sometimes used to describe lesbians who are more masculine (act or dress more like men). However, "queer" and "dyke" are sometimes used against gay people as insults, so they can sometimes be offensive.


title: Homosexuality

text: When homosexual people keep their sexual orientation a secret, they are said to be "in the closet". "Out" or "out of the closet" is a slang term that means a homosexual person is open about their sexual orientation. This means they do not hide the fact that they are homosexual. Some gay and lesbian people stay in the closet because of fear of what would happen or because they live in a place that is not safe for homosexual people.


title: Homosexuality

text: Sometimes people who are 'out' also say they are 'proud'. "Out" means they are not hiding their sexual orientation. "Proud" means that they are pleased about it. "Proud" or "Pride" has a special meaning in the LGBT community. It means they are celebrating and being happy that they are homosexual. It is not 'pride' meaning that they have done something to be proud of, but 'pride' meaning the opposite of shame. Many cities have "Pride Parades". These used to be protest marches. Today, they are usually celebrations of the LGBT community. They usually occur in June, in memory of the 'Stonewall Riots' that happened in New York City in 1969. These riots happened because police harassed and arrested people for being homosexual. 'Stonewall' or the 'Stonewall Riots' are sometimes called the start of the LGBT rights movement.


title: Homosexuality

text: The causes of homosexuality and bisexuality are controversial (people do not agree on them). The causes of homosexuality are not all understood, but genetics and the effects of the prenatal environment and hormones (when a baby is growing in its mother) are thought to be causes. There is not much evidence that the social environment is a cause of homosexuality. Scientists also show that homosexuality happens not only in humans. Some animals (like penguins, chimpanzees, and dolphins) often show homosexuality, and some (rams) even for lifelong periods as is the case with humans.


title: Homosexuality

text: Doctors used to treat gay people as if they had mental illnesses. However, homosexuality is no longer called a disease by doctors in many countries. There are some religious and non-religious groups who still try to 'cure' homosexuality. This is sometimes called 'conversion therapy'. In therapies like this one, homosexual individuals have tried to become heterosexual and have even claimed they were changed, but most people do not believe it is possible.


title: Homosexuality

text: Conversion therapy or reparative therapy aims to change people's sexual orientation from homosexual to heterosexual. It is condemned by medical and psychiatry groups such as the American Psychological Association, American Psychiatric Association, Royal College of Psychiatrists, National Association of Social Workers, Royal College of Nursing, and the American Academy of Pediatrics. These scientific and educated groups are concerned that such therapy is a violation of the ethical principles of health care, and violates human rights.


title: Homosexuality

text: Many people believe that it is unfortunate to discuss causes of homosexuality and bisexuality without discussing causes of heterosexuality, too. Although it is easy to understand why heterosexuality exists (heterosexual sex produces babies), that does not explain how the brain develops to produce heterosexual people. Heterosexuality, homosexuality, and bisexuality all have causes, and some people believe that to discuss only the causes of homosexuality and bisexuality suggests that there is something wrong with people who have those orientations.


title: Homosexuality

text: Gay people can fall in love and have lifelong relationships. In most countries, they cannot legally marry their partners. However, they still have relationships in the same way as heterosexual people.


title: Homosexuality

text: Some homosexual people have wedding ceremonies even though governments do not recognize or accept them. They may call their partner a spouse, wife, or husband despite the law.


title: Homosexuality

text: But to them, the important part about marriage is not just the name. Married people get many benefits from being married. Depending on the country, these benefits can include paying less taxes, getting their spouse's insurance, inheriting property, social security benefits, having or adopting children together, emigrating to a spouse's country, being able to make choices for a sick spouse, or even being allowed to visit a sick spouse who is in a hospital.


title: Homosexuality

text: Today there are numerous countries that allow homosexual people to marry, including: Argentina, Australia, Belgium, Brazil, Canada, Denmark, England, Finland, France, Iceland, Ireland, Luxembourg, Netherlands, New Zealand, Norway, Portugal, Republic of Ireland, Scotland, Spain, South Africa, Sweden, Uruguay, the United States and Wales. The Netherlands was first in 2001. It is also legal in six Native American tribes.


title: Homosexuality

text: Instead of marriage, some countries or states offer homosexuals civil unions or domestic partnerships. This gives them some of the protections and benefits of marriage, but not all. Civil unions and domestic partnerships are sometimes seen by the LGBT community as being 'second class' (not as good as 'first class'). They do offer some benefits for gay and lesbian couples, but they also suggest that these couples are not as important or valid as heterosexual couples. Some people even say this is like the "separate but equal" rules that were used to segregate people by race in the United States. They believe that separate is "never" equal and homosexuals should not accept being second class citizens.


title: Homosexuality

text: Many religions teach that homosexual sex is a sin. Such religions traditionally include Islam, Christianity and Judaism. Usually, it is only the act of sexual intercourse that is considered sinful and not natural. Not all believe the attraction, is sinful, just the actions in response to the desire.


title: Homosexuality

text: However, some denominations (different parts) of these religions and some eastern religions now accept homosexuality. There are several other religions that are accepting of homosexuality, particularly new religions. There are also some religions which are indifferent to homosexuality, such as Zoroastrianism and Jainism.


title: Homosexuality

text: In many countries, homosexual people are discriminated against. A homosexual person can be fired from a job because they are gay, even if they are a good worker. Homosexual people can be denied renting a home or being able to eat in a restaurant because of their sexual orientation.


title: Homosexuality

text: In some countries, homosexual people can experience violence. For example, Islamic law is used in some places to kill homosexuals or place them in jail. Some groups believe over 4,000 homosexual people have been killed in Iran since 1979 because of their sexual orientation. In 2005, after fourteen months of prison and torture, two teenage boys were hanged in Iran for homosexuality.


title: Homosexuality

text: In modern times, homosexuality has become more accepted in Western countries. Most western countries have laws that protect homosexuals from violence and discrimination.


title: Homosexuality

text: In the United Kingdom, homosexuality used to be a crime. Oscar Wilde, the famous Irish writer was imprisoned for it, and as a result, it destroyed his reputation and career as a wit and playwright. Alan Turing, the man who helped the Allies in World War II by breaking the Enigma Code used by the Germans, was convicted of this crime and according to some speculations he ultimately killed himself over the effects of the attempt to cure his homosexuality.


title: Homosexuality

text: Today in the United Kingdom, homosexual people are safer. Homosexual sex between adults is not a crime. Gay and lesbian couples can marry. Gay people can be in the military.


title: Homosexuality

text: In most of the world, homosexual people still do not have the same rights and freedoms that heterosexuals have.


title: Homosexuality

text: Homosexual behaviour has also been seen in animals. Homosexual, transgender and bisexual behaviour includes sex, courtship, affection, pair bonding, and parenting. Homosexual behaviour is widespread among animals. Bruce Bagemihl did research in 1999. It shows that homosexual behaviour has been observed in close to 1500 species, from primates to gut worms, and is well documented for 500 of them. The sexual behaviour of animals takes many different forms, even within the same species. The motivations for these behaviours are only partly known, mainly because the respecive species has not been fully studied yet. According to Bagemihl, "the animal kingdom [does] it with much greater sexual diversity—including homosexual, bisexual and nonreproductive sex—than the scientific community and society at large have previously been willing to accept."


title: Homosexuality

text: There are national and international groups or organizations for the LGBT community. These organizations are often political. They fight for the rights and safety of homosexuals.


title: Mercury (planet)

text: Mercury is the smallest planet in the Solar System. It is the closest planet to the sun. It makes one trip around the Sun once every 87.969 days.


title: Mercury (planet)

text: Mercury is bright when we can see it from Earth. It has an apparent magnitude ranging from −2.0 to 5.5. It cannot be seen easily because it is usually too close to the Sun. Because of this, Mercury can only be seen in the morning or evening twilight or when there is a solar eclipse.


title: Mercury (planet)

text: Less is known about Mercury than about other planets of our Solar System. Even with telescopes only a small, bright crescent can be seen. It is also hard to put a satellite in orbit around it. Two spacecraft have visited Mercury. The first one was Mariner 10. It only made a map of about 45% of the Mercury's surface from 1974 to 1975. The second is the MESSENGER spacecraft, which finished mapping Mercury in March 2013.


title: Mercury (planet)

text: Mercury looks like Earth's Moon. It has many craters and smooth plains. It has no moons and little atmosphere as we know it. However, Mercury does have an extremely thin atmosphere, known as an exosphere. Mercury has a large iron core. Because of this Mercury has a magnetic field about 1% as strong as that of the Earth. It is a very dense planet because its core is large.


title: Mercury (planet)

text: Temperature at the surface can be anywhere from about 90 to (−183 °C to 427 °C, −297 °F to 801 °F), with the subsolar point being the hottest and the bottoms of craters near the poles being the coldest.


title: Mercury (planet)

text: Known sightings of Mercury date back to at least the first millennium BC. Before the 4th century BC, Greek astronomers thought that Mercury was two different objects: The one that they were only able at sunrise, they called Apollo; the other one that they were only able to see at sunset, they called Hermes. The English name for the planet is from the Romans, who named it after the Roman god Mercury. The symbol for Mercury is based on Hermes' staff.


title: Mercury (planet)

text: Even though Mercury is the closest planet to the Sun, it is not the hottest. This is because it has no greenhouse effect. The heat that the Sun gives it, quickly escapes into space. The hottest planet is Venus.


title: Mercury (planet)

text: Mercury is one of four inner planets in the Solar System. It is a terrestrial planet like Earth. It is the smallest planet in the Solar System. It has a radius of . Mercury is even smaller than some of the largest moons in the solar system, such as Ganymede, the largest moon of Jupiter and Titan, the largest moon of Saturn. However, it has in 2.2 times greater mass than Ganymede and around 2 times heavier than Titan. Mercury is made of about 70% metallic and 30% silicate material. Mercury has the second highest density in the Solar System at 5.427 g/cm³, only a little bit less than Earth’s.


title: Mercury (planet)

text: Mercury's surface looks like the surface of the Moon. It has plains that look like mares and has lots of craters. Mercury was hit by a lot of comets and asteroids 4.6 billion years ago. Mercury was also hit during a period called the Late Heavy Bombardment. Mercury has many craters because its atmosphere is too faint to slow objects down. Images from "MESSENGER" have shown that Mercury may have shield volcanoes.


title: Mercury (planet)

text: The surface temperature of Mercury ranges from 100 to 700 K (−173 to 427 °C; −280 to 800 °F) at the most extreme places. Even though the temperature at the surface of Mercury in the day is very high, observations suggest that there is frozen water on Mercury.


title: Mercury (planet)

text: Mercury is too small and hot for its gravity to keep any thick atmosphere for a long time. It does have a thin exosphere that is made up of hydrogen, helium, oxygen, sodium, calcium, potassium. This exosphere is blown away and replenished from lots of sources. Hydrogen and helium may come from the solar wind. Radioactive decay of elements inside the crust of Mercury is another source of helium, and also sodium and potassium.


title: Mercury (planet)

text: Mercury has the most eccentric orbit of all the planets in the Solar System. It has an eccentricity of 0.21. It ranges from 46,000,000 to 70,000,000 km (29,000,000 to 43,000,000 mi) away from the Sun. Mercury takes 87.969 Earth days to go around the Sun. Mercury's axial tilt is 0.027 degrees.


title: Mercury (planet)

text: In the future, because Mercury's orbit's is very eccentric and Jupiter's huge gravity, its orbit may become unstable and the following things may happen:


title: Mercury (planet)

text: The first spacecraft to visit Mercury was NASA's Mariner 10. It stayed in Mercury's orbit from 1974 to 1975. Mariner 10 took the first close-up pictures of Mercury's surface. It showed many features, such as the craters. Unfortunately, the same side of Mercury was day each time Mariner 10 flew close to Mercury. This made observing of both sides of Mercury impossible. In the end, less than 45% of the Mercury's surface was mapped.


title: Mercury (planet)

text: Mariner 10 came close to Mercury three times. At the first time, it found a magnetic field, which surprised planetary geologists because Mercury's rotation was too slow to create a magnetic field. The second time was mainly used to take pictures of Mercury's surface. At the third time, it got more information about the magnetic field. It showed that the Mercury's magnetic field is like the Earth's magnetic field.


title: Mercury (planet)

text: On March 24, 1975, eight days after its last close fly by, Mariner 10 ran out of fuel. Because its orbit could no longer be controlled, mission controllers shut down the probe . Mariner 10 is thought to still be orbiting the Sun.


title: Mercury (planet)

text: The second satellite to visit Mercury is NASA's MESSENGER. It stands for MErcury Surface, Space ENvironment, GEochemistry, and Ranging. It was launched on August 3, 2004. It made a fly-by of Earth in August 2005. It made another fly-by of Venus in October 2006. It made its first fly-by of Mercury happened on January 14, 2008, a second on October 6, 2008, and a third on September 29, 2009. It made a map of most of Mercury that "Mariner 10" didn't map. The first image of Mercury orbiting the Sun was gotten on March 29, 2011.


title: Mercury (planet)

text: MESSENGER was made to study Mercury's high density, the history of Mercury's geology, its magnetic field, the structure of its core, if it has ice at its poles, and where its thin atmosphere comes from. "MESSENGER" crashed into Mercury's surface on April 30, 2015.


title: Mercury (planet)

text: The European Space Agency and the Japanese Space Agency made and launched a spacecraft called "BepiColombo." It will orbit Mercury with two probes: one to map the planet and the other to study its magnetosphere. It was launched on October 20, 2018. "BepiColombo" is expected to reach Mercury in 2025. It will release the probe that will study the magnetosphere into an elliptical orbit. It will then release the probe the will make a map of Mercury into a circular orbit.


title: Rice

text: Rice ("Oryza sativa") is a type of cereal and food. In origin, it is a swamp grass. It is eaten as staple food in many parts of Asia. It is grown in warm parts of the world, mainly Asia, Africa, northern Italy, and the west coast of North America.


title: Rice

text: Rice accounts for 80% of the calories eaten in Asia, or one-fifth of the calories eaten worldwide by humans. It is the agricultural commodity with the third-highest worldwide production (rice, 741.5 million tonnes in 2014), after sugarcane (1.9 billion tonnes) and maize (1.0 billion tonnes). However, judged by value, the world trade in wheat is greater than all other crops combined. All these cereals are grasses.


title: Rice

text: Rice used to be the main diet in many countries. Various kinds of food processing prepare rice for eating. It is usually cooked. In some areas, such as Spain, rice is first fried in olive oil or butter, then cooked with water or soup. In other areas, such as India, rice is eaten with sauce, curry, or soup. Rice can also be used to make alcohol, such as Japanese sake rice wine.


title: Rice

text: Rice is believed to have been first grown in ancient southern China and India around 2500 BC. Rice-growing was brought to Japan possibly in the 1st century BC, and became popular during the 2nd century and the 3rd century. From India, rice spread to southern Europe and Africa.


title: Rice

text: Iran is also a producer of rice in Asia with a production of 2.4 MMT. The food consumption pattern of people in Iran shows that Iranians consume an average of 100 g of rice per day. Rice is the second most popular and favorite food in Iran after bread.


title: Rice

text: Rice is usually planted in a flat field filled with water. Before cropping, the water is drained from the field. Before farmers developed a good farming system and fertilizers, they used to let lands rest for 1 to 2 years while farming in other lands.


title: Rice

text: In some hot areas, close to the equator, farmers do double-cropping which means raising two crops in one year.


title: Rice

text: Rice contains a lot of carbohydrates. There are different ways of milling rice. Brown rice has only had the outer layer removed. It contains more fibre than the completely milled white rice.


title: Rice

text: There are several grains called "rice": they have been cultivated for thousands of years. There are a huge number of varieties.


title: Rice

text: Asian rice ("Oryza sativa)" is most widely known and most widely grown, with two major subspecies and over 40,000 varieties. Also notable are varieties of African rice ("Oryza glaberrima") and wild rice (genus "Zizania"). Rice may vary in genetics, grain length, color, thickness, stickiness, aroma, growing method, and other characteristics.


title: Rice

text: Rice can be divided into different categories on the basis of each of its major characteristics. The two subspecies of Asian rice, "indica" and "japonica" have different length and stickiness. Indica rice is long-grained and unsticky, while japonica is short-grained and sticky.


title: Rice

text: The new strain, part of the Green Revolution, had defects. It lacked taste, and the team spent 20 years improving its quality, and its resistance to fungi and pests. The team's later work was to reduce its bad effect on diabetes type 2 and on its vitamin A content.


title: Student

text: A student is a person who goes to school to learn something. Students can be children, teenagers, or adults who are going to school, but it may also be other people who are learning, such as in college or university. A younger student is often called a pupil. Usually, students will learn from a teacher or a lecturer if at university. They also do much reading. A student can also be a person studying for a specific profession.


title: Robert G. Heft

text: Robert G. "Bob" Heft (January 19, 1942 – December 12, 2009) was the designer of the current United States 50-star flag. He has also designed a 51-star flag that would be used if a new state joins the United States. He was born in Saginaw, Michigan.


title: Robert G. Heft

text: Heft claimed to have designed the current United States flag as a school project in Lancaster, Ohio, when he was 17 years old. He received a B- for his project from his teacher, Stanley Pratt. After talking about the project, he reached an agreement with his teacher that, if the flag was selected as the official flag by the United States Congress, he would get a better grade for the project. Heft stated that his design was chosen out of more than 1,500 designs that were given to United States President Dwight D. Eisenhower, and his teacher changed his grade to an A. This claim is now in dispute and is believed to be a hoax.


title: Robert G. Heft

text: After graduating from college, he became a high school teacher and later a college professor. He was also mayor of Napoleon, Ohio for 28 years.


title: Robert G. Heft

text: After years of combating diabetes, Heft died on December 12, 2009, from a heart attack while living in Saginaw. He was 67 years old.


title: Marie Curie

text: Maria Salomea Skłodowska–Curie (Marie Curie) (7 November 1867 – 4 July 1934) was a Polish physicist, chemist and feminist. She did research on radioactivity. She was also the first woman to win a Nobel Prize. She was the first woman professor at the University of Paris. She was the first person to win two Nobel Prizes. She received a Nobel Prize in physics for her research on uncontrolled radiation, which was discovered by Henri Becquerel.


title: Marie Curie

text: She died because of too much exposure to radiation in her laboratory because she had no protection against the effects of radiation.


title: Marie Curie

text: Curie was born on 7 November 1867 in Warsaw, Poland. She lived there until she was 22. Her original name was Maria. Marie Curie was the fifth child in her family. At the age of ten, her sister Zofia died. Her mother died two years later. Her father was a math teacher. As a young girl, she was interested in physics. She was top of her high school class. She graduated at 15. Marie became a teacher so she could earn money to go to school in Paris, France. She also went to an unaccredited college in Poland. Eventually, she left Poland and went to France under the name “Marie" after one of her big sisters gave her the chance. In Paris, she earned higher degrees and did her important scientific work. She founded the Curie Institutes in Paris and Warsaw.


title: Marie Curie

text: Curie did many things. She and her husband created a theory of "radioactivity" (a term made by her and her husband Pierre Curie). They found different ways to separate radioactive isotopes and discovered two new elements: radium and polonium. The term polonium was named after Poland, her home country. She used her own studies in radioactivity to develop a new treatment for cancer. These treatments used the radioactive isotopes. She was the first woman to win the Nobel Prize. She was the first person to win two Nobel Prizes.


title: Marie Curie

text: Curie discovered radium. It is one of the most radioactive and dangerous metals. She shared this discovery with Pierre Curie and Gustave Bemont. The three found radium in 1898. They discovered it when using a uranium ore. It gave off a lot of radiation. They decided that it was coming from more than uranium. The group found radium in the uranium. Radium is now used for many different things. For example, doctors used to use it to kill cancer cells. Radium was found in paint and watches. Many workers who made radium-containing products developed bone cancer.


title: Marie Curie

text: Even though Curie became a French citizen, Curie never lost her Polish identity. She graduated first in her class in 1893. One year later she earned a master's degree in mathematics. Later, she met her husband, Pierre, at the Municipal School of Industrial Physics and Chemistry. They were married in July 1895 after only one year. They also started to work together on scientific discoveries. Marie and Pierre had their first daughter, Irene, in 1897. Their second daughter, Eve, was born in 1904. Pierre died on April 19, 1906, after he was hit by a horse-drawn wagon.


title: Marie Curie

text: After the war, Marie started to raise money for a hospital. The hospital raised money for radiation research. She was invited to tour the United States to recommend and speed up her project. She sailed for the United States in 1921. She collected enough money and equipment for a new laboratory. She then started speaking at meetings to raise more money and became a celebrity. She also supported world peace by serving on the council of the League of Nations.


title: Marie Curie

text: Near the 1920s, Curie and many of her colleagues began to suffer from symptoms of cancer. Curie began to lose her sight. Cataract surgeries to try to bring back her sight did not help. Curie knew that the element (radium) she discovered might have been causing the symptoms, but she did not want to admit it to herself or others. In the early 1930s, Curie’s health started to quickly get worse. Doctors diagnosed her with pernicious anemia. Pernicious anemia is a blood anemia that happens when someone is overly exposed to radiation. The doctors didn’t tell the public or Curie herself what was going on. On July 4, 1934, at 66 years old, she died in a Sanitorium at the French Alps. She was then buried next to her husband in Sceaux, France. Marie Curie was a physicist and chemist best known for her work on radioactivity; however, she also discovered the elements polonium and radium. She was awarded two Nobel Prizes — one in physics which she won jointly with her husband and Henri Becquerel, and another in chemistry — and was the first person to win two Nobel Prizes. She is still one of only four people (along with Linus Pauling, John Bardeen and Frederick Sanger) to accomplish that feat. Curie is responsible for establishing the theory of radioactivity, but unfortunately she unwittingly also discovered the fatal effect radioactivity can have on your health; she died on July 4, 1934, of aplastic anemia caused by radiation exposure.


title: Volcanic eruption

text: A volcanic eruption occurs when hot materials from the Earth's interior are thrown out of a volcano, Lava, rocks, dust, and gas compounds are some of these "ejecta".


title: Volcanic eruption

text: Eruptions can come from side branches or from the top of the volcano. Some eruptions are terrible explosions that throw out huge amounts of rock and volcanic ash and can kill many people. Some are quiet outflows of hot lava. Several more complex types of volcanic eruptions have been described by volcanologists. These are often named after famous volcanoes where that type of eruption has been seen. Some volcanoes may show only one type of eruption during a period of activity, while others may show a range of types in a series.


title: Volcanic eruption

text: The Volcanic Explosivity Index (commonly shortened VEI) is a scale, from 0 to 8, for measuring the strength of eruptions. It is used by the Smithsonian Institution's Global Volcanism Program to assess historic and prehistoric lava flows. It works in a way similar to the Richter scale for earthquakes: each interval in value is a tenfold increase in magnitude (it is logarithmic). Most volcanic eruptions are of VEIs between 0 and 2.


title: Neil Armstrong

text: Neil Alden Armstrong (August 5, 1930 – August 25, 2012) was an American astronaut and engineer and is known as the first person to walk on the moon. On July 20, 1969, Neil Armstrong and Buzz Aldrin landed on the moon in a small spacecraft that had been sent to the moon using the Saturn V rocket. The mission was called Apollo 11. They both walked on the moon, and millions of people watched and heard this event on live television.


title: Neil Armstrong

text: He earned a BSc degree in Aeronautical Engineering from the Purdue University in 1955 and an MSc degree in Aerospace Engineering from the University of Southern California. In 1970 he received an Honorary Doctorate of Engineering from the Purdue University. In 1971 he became professor of aerospace engineering at the University of Cincinnati. He joined the National Aeronautics and Space Administration, then known as the National Advisory Committee for Aeronautics, serving as a civilian test pilot at Edwards Air Force Base, Lancaster, Calif.


title: Neil Armstrong

text: In 2005, he received the Honorary Doctorate of letters from the University of Southern California. The "Houston Chronicle" newspaper reported on October 1, 2006, that Australian computer programmer Peter Shann Ford found the missing "a" from Armstrong's famous first words on the Moon. Ford reported that he downloaded the audio recording from a NASA web site and analyzed it using editing software originally intended for use with hearing disabled people. Armstrong is said to have been pleased with Ford's finding of the missing "a". I’m going back to the moon


title: Neil Armstrong

text: Prior to being an astronaut, Armstrong was called to Pensacola Naval Air Station in Florida in 1949 before he could complete his degree. There he earned his pilots wings at 20 years of age, making him the youngest flyer in his squadron. While studying for his aeronautical engineering degree, the Korean War broke out in 1950, in which he flew 78 combat missions. His plane was shot down once and he was also awarded 3 Air Medals. Later, he became a skilful test pilot, flying right to the atmosphere’s edge, at , in the experimental rocket powered aircraft the X-15.


title: Neil Armstrong

text: Armstrong went on his first mission into space on the 16th of March 1966, in the spacecraft Gemini 8, as the command pilot. He docked the Gemini 8 successfully with an Agena target craft that was in orbit already. Although the docking was smooth enough, while the spacecrafts orbited together, they started to roll and pitch. Armstrong then managed to undock the Gemini, and regained control of the spacecraft by using the retro rockets. However, this resulted in the astronauts having to make an emergency landing into the Pacific Ocean. Following the fatal explosion of the space shuttle "Challenger" in January 1986, Armstrong was appointed deputy chief of the presidential commission set up to investigate the disaster.


title: Neil Armstrong

text: He spoke those words when he set his foot on the moon. He wanted to say "That's one small step for "a" man…", but for some reason the "a" was never spoken. Armstrong thought he had said it. Listening to the audio shows that the "for" runs on smoothly, giving no time for "a" to be spoken. Armstrong prefers written quotations to include the "a" in parentheses.


title: Neil Armstrong

text: Armstrong was married to Janet Shearon from 1956 until they divorced in 1994, they had three children; Mark, Eric, and Karen. Lastly he married Carol Held Knight from 1994 until his death in 2012.


title: Neil Armstrong

text: Some years after returning from the Moon, he visited the 2,000 year-old King Herod's Temple Mount in the city of Jerusalem. While he was there, Neil Armstrong said it was more exciting to step on the stone steps where Jesus Christ walked than even stepping on the Moon.


title: Neil Armstrong

text: Armstrong died on the morning of August 25, 2012 from complications of a blocked coronary artery after surgery in a hospital in Cincinnati, Ohio. He was 82 years old. In July 2019, "The New York Times" reported that Armstong died after nurses removed the wires connected to his temporary pacemaker. He began to bleed internally and his blood pressure dropped and the doctors did not perform surgery on time to save him.


title: Manhattan

text: Manhattan is one of the five boroughs that make up New York City, and is the center of the New York metropolitan area. It is also located over the same area as a county of New York state called New York County. Although it is the smallest borough, it is the most densely populated borough. Most of the borough of Manhattan is on Manhattan Island, but the Marble Hill neighborhood is part of the mainland United States (by way of the Bronx). Several smaller islands, including Roosevelt Island, are also part of Manhattan.


title: Manhattan

text: The Dutch bought it from the Native Americans and called it New Amsterdam, then the English took it over and changed the name to New York. The name "Manhattan" comes from the Munsi language of the Lenni Lenape meaning "island of many hills". Other theories say that it comes from one of three Munsi words. "Manahactanienk" meaning "place of inebriation". Other possibilities are "manahatouh" meaning "a place where wood is available for making bows and arrows" and "menatay" meaning simply "the island."


title: Manhattan

text: Manhattan is an important commercial, financial, and cultural center of both the United States and the world. Most major radio, television, and telecommunications companies in the United States are based there, as well as many news, magazine, book, and other media publishers. Manhattan has many famous landmarks, tourist attractions, museums, and universities. It also has the headquarters of the United Nations.


title: Manhattan

text: Before colonization, the Lenape Indians lived in the area that is now called Manhattan. In 1524, Lenape people in canoes met Giovanni da Verrazzano, the first European explorer to pass New York Harbor, although he may not have entered the harbor past the Narrows. Henry Hudson, an Englishman who worked for the Dutch East India Company, made the first map of the area.


title: Manhattan

text: In the 1620s, the first large European colony was started in New Netherland, when the Dutch began trading fur on Governors Island. In 1625, the Dutch chose Manhattan Island to build Fort Amsterdam, a citadel for the protection of the new arrivals. It would later be called New Amsterdam (Dutch: "Nieuw Amsterdam"). The creation of New Amsterdam was recognized as the birth of New York City.


title: Manhattan

text: On May 24, 1626, Manhattan was bought from the Native Americans living on the island. The price was trading goods worth 60 guilders, which was worth about 24 dollars at the time. The currency calculations from the International Institute of Social History in Amsterdam say that 60 guilders in the 1620s cost around $1000 now.


title: Manhattan

text: In 1647, Peter Stuyvesant became the last Dutch Director General of the colony. New Amsterdam was considered an official city on 3 February 1653. In 1664, the British conquered New Netherland and renamed it "New York" after the English King James II, then known as Duke of York and Albany. Stuyvesant and his council made a deal with the British where New Netherlanders were promised liberties, including freedom of religion, under British rule. In August 1673, the Dutch took control of the island again, calling the city "New Orange" (Dutch: "Nieuwe Oranje"). The Dutch lost control of New Netherland forever to the English in November 1674 by treaty.


title: Manhattan

text: Manhattan was the center of many campaigns, battles and meetings during the American Revolution. In 1765, all of the colonies worked together for a unified political aim when the Stamp Act Congress (meeting) of representatives from across the Thirteen Colonies was held in New York City to write The Declaration of Rights and Grievances.


title: Manhattan

text: The Sons of Liberty, a Boston based group, were part of a long-term battle with British authorities over liberty poles that were sometimes raised by the Sons of Liberty and cut down by the British. The disputes ended when the revolutionary New York Provincial Congress took power in 1775.


title: Manhattan

text: Manhattan was the center of a series of large battles in the early American Revolutionary War. These battles were called the New York Campaign, where British forces and colonists fought for control of New York City and the state of New Jersey. The rebel Continental Army, led by George Washington, had to leave Manhattan after losing the Battle of Fort Washington on 16 November 1776. Shortly after, Manhattan was greatly damaged by the Great Fire of New York in 1776.


title: Manhattan

text: Victory gave the British control of the area. They used the city as the center for political and military activities for the rest of the war. Loyalists from elsewhere came to the city as refugees from the Rebels and to join the war.


title: Manhattan

text: Years later, Washington came back to Manhattan with his army. On Evacuation Day, the last British occupation forces left the city on 25 November 1783. On 30 April, 1789, Washington was inaugurated (officially became) the first president of the United States and took his oath of office at Federal Hall on Wall Street.


title: Manhattan

text: In the early 19th century, Manhattan grew in population and economically. Another great fire in 1835 destroyed much of the city but it was soon rebuilt. Because of the Great Irish Famine, a lot of Irish people emigrated (left their country) to live in New York; they made up for 25% of Manhattan's population at the time. Many of the Irish people lived in a part of the Lower East Side known as the Bowery or in another section called Five Points.


title: Manhattan

text: After the Civil War, many immigrants of Italian, Polish and Jewish backgrounds came to Manhattan and lived in tenements in a part of the city called the Lower East Side. Over a million people lived in the area at one point.


title: Manhattan

text: An Irish political machine called Tammany Hall was very important to New York City during the Gilded Age. With the support of mostly Irish immigrants, it grew as a political machine. The support helped win the election for the first Tammany mayor, Fernando Wood, in 1854. Central Park, which opened to the public in 1858, became the first landscaped park in any American city and the country's first public park.


title: Manhattan

text: The rate of immigration from Europe shot up after the Civil War, and New York became the most popular state for immigrants in the United States. Because of this, the French built and gave New York the Statue of Liberty on October 28, 1886. Soon after, the boroughs of Manhattan and Brooklyn were combined into one city.


title: Manhattan

text: In the beginning of the 20th century, many new things were built in the city, like skyscrapers and the New York City Subway. The first subway transit center, the Interborough Rapid Transit or "IRT", opened to the public in 1904. The installation of the Subway helped tie the new city together, as did new bridges to Brooklyn. In the 1920s, many African-Americans came to live in Manhattan during the Great Migration from the American South, and the Harlem Renaissance. New York City became the most populous city (city with the most people) in the world in 1925, overtaking London, which had held the title for a century.


title: Manhattan

text: Between World War I and World War II, reformist Fiorello La Guardia was elected as the new mayor in 1933 and took office in 1934, marking the fall of Tammany Hall after 80 years of dominating politics in New York City. Once the city's demographics were steadier, labor unionization provided protection and affluence to the working class. Despite the Great Depression, some of the world's tallest skyscrapers of the time were built in Manhattan during the 1930s, including many Art Deco masterpieces that are still part of the city's skyline today. The most well-known structures are Empire State Building, the Chrysler Building, and the GE Building.


title: Manhattan

text: Following the end of World War II, a lot of veterans came home to the United States. This led to the development of private communities that were intended to be sold or rented out to returning soldiers, resulting in an economic boom. An example of one of the communities built to attract veterans looking for homes is Stuyvesant Town—Peter Cooper Village, which opened in 1947. In 1951, the United Nations relocated from its first headquarters in Queens, to the East Side of Manhattan.


title: Manhattan

text: Population and industry began to decline in the 1960s. The Stonewall riots were a series of violent demonstrations by members of the gay community. By the 1970s, the city had gained a reputation as a graffiti-covered, crime-ridden relic of history. In 1975, the city government went bankrupt (ran out of money), and its pleas for financial help were rejected at first. On 30 October 1975, the New York Daily News reported the event with the headline as "Ford to City: Drop Dead". The city received a federal loan and debt restructuring. After the economic downfall and recovery, New York State kept a close watch on New York City's economy.


title: Manhattan

text: In the 1980s, Wall Street was revived from its slump, and the city reclaimed its role at the center of the worldwide financial industry. During this time, Manhattan was also at the heart of the AIDS crisis, with Greenwich Village being a major center of the epidemic. "Gay Men's Health Crisis" (GMHC) and "AIDS Coalition to Unleash Power" (ACT UP) were organizations that were started because of the crisis. Their purpose was to advocate on behalf of those AIDs victims.


title: Manhattan

text: Crime rates began to drop greatly in the 1990s. Murder rates were 537 in 2008 compared to 2,245 in 1990. The crack epidemic and its associated drug-related violence had died down, and was under great control by the city. Many people who had moved out of the city came back because the city once again became the destination of immigrants from around the world, joining with low interest rates and Wall Street bonuses to fuel the growth of the real estate market.


title: Conservatism

text: Conservatism is a type of political belief that supports emphasis on traditions and relies on the individual to maintain society. The term was first used by François-René de Chateaubriand in 1818, during the Bourbon Restoration, which wanted to roll back the policies of the French Revolution. The term is associated with right-wing politics. It has been used to describe a wide range of views. There is no single set of policies that are regarded as conservative because the meaning of conservatism depends on a given place and time, although most Conservatives oppose Modernism in some way and want to go back to old values.


title: Conservatism

text: In Western culture for example, Conservatives try to maintain things like organized religion, property rights, parliamentary government and family values.


title: Conservatism

text: Conservatism tends to support the notion of faith, particularly in Abrahamic traditions in countries where those are the dominant religions. In England, the publication of Edmund Burke’s book "Reflections on the revolution in France" suggested people should be satisfied and advocated a caring government. The two ideas go together.


title: Conservatism

text: Some conservatives seek to keep things as they are, while others want a return to the way things were at an earlier time. This is often called reactionary conservatism. A conservative party in England formed which wanted better co-operation between rich and poor, democracy, and some aspects of a welfare state. This was also favored by conservatives in France and other parts of Europe.


title: Conservatism

text: In Brazil, conservatism comes from its Portuguese roots, often being Evangelical, such as President Jair Bolsonaro.


title: Conservatism

text: Conservatives in India are pro-Hindu, anti-Pakistan, and are socially conservative. The Bharatiya Janata Party is the biggest conservative party in India, lead by Narendra Modi.


title: Conservatism

text: In the United States, conservatives worry about centralism, do not trust the welfare state, and consider business people trustworthy on wages and prices. During the 20th century the Republican Party became a Conservative political party in the United States.


title: Hindi

text: Hindi, historically known as Hindui (हिंदुई), is an Indo-Aryan language. It is the main language in India. About 800 million people speak Hindi in India. The Devanāgarī script is used to write Hindi. Previously Hindi was known as "Hindui".


title: Hindi

text: Hindi is widely written, spoken and understood in North India and some other places in India. In 1997, a survey found that 45% of Indians can speak Hindi. It has taken words from the Dravidian languages of South India, as well as the Arabic, Persian, Chagatai, English and Portuguese languages.


title: Hindi

text: Hindi and Urdu were considered the same language but have evolved into separate dialects. However, to this day, both languages are mutually intelligible, meaning their speakers can understand each other without knowing the other language. Urdu, however, is written in the completely different Arabic alphabet.


title: Hindi

text: Hindi developed from Sanskrit, the ancient Indo-Aryan language of India. Hindi started to develop in the 7th century as "Apabhramsha" and became stable by the 10th century. Some famous Hindi poets are Tulsidas and Kabir.


title: Hindi

text: Dialects of Hindi include: Avadhi, Braj, Bhojpuri, Bundeli, Bagheli, Chhattisgarhi, Dogri and Marwari.


title: Hindi

text: Hindi is also spoken with regional accents like Haryanvi and Rajasthani. Bombay Hindi is spreading because Bollywood films use it.


title: Hindi

text: Hindi Diwas is an annual celebration on 14th September. It commemorates the law of 1949 that made Hindi the legal language of the Republic.


title: Gregorian calendar

text: The Gregorian calendar is the calendar that is used throughout most of the world. It began being used in 1582. It replaced the previous Julian calendar because the Julian calendar had an error: it added a leap year (with an extra day every four years) with no exceptions. The length of the Julian year was exactly 365.25 days (365 days and 6 hours), but the actual time it takes for the Earth to go around the Sun once is closer to 365.2425 days (about 365 days, 5 hours and 49 minutes). This difference is about eleven minutes each year.


title: Gregorian calendar

text: This made the seasons get out of track with the calendar. For example, as the centuries went by, the equinox (when day and night are the same length) was happening earlier and earlier than its traditional date, March 21. It was the calendar that was wrong, not the earth's orbit. By the 1500s, it was starting around March 11, ten days 'too early' according to the calendar. To farmers, this did not matter because they worked to the seasons rather than to the calendar. But it mattered a lot to the Christian church because the date of Easter is calculated from the equinox being on 21 March. So Pope Gregory XIII declared that the calendar must skip ten days in 1582.


title: Gregorian calendar

text: To make sure that the mistake did not happen again, they revised the 'leap year rule'. Until then, every fourth year had February 29, without exception. The change was that there would be no February 29 for every year that ends in 00 - unless it could be divided by 400. So the year 2000 was a leap year, because it could be divided by 400, but 1700, 1800, and 1900 would be common years, with no February 29.


title: Gregorian calendar

text: The official change took place the following October, when Thursday, 4th was followed by Friday, 15th.


title: Gregorian calendar

text: If February has 29 days, then the year is called a "leap year" and it is 366 days long. A leap year usually happens once every four years. The most recent leap year was 2020, and the next leap year is 2024.


title: Gregorian calendar

text: The Pope's instruction only applied to the Catholic Church, countries made their own laws. But Europe's Catholic countries decided to follow his lead. Spain, Portugal, and Italy started to use the new calendar on Friday, October 15, 1582, following Julian Thursday, October 4, 1582. In Europe's Protestant countries, people feared that the new calendar was an attempt by the Catholic Church to silence their movement. Since the Great Schism, Europe's Eastern Orthodox churches also ignored the Pope's decision and many continue to use the Julian calendar even today.


title: Gregorian calendar

text: England and the rest of the British Empire (including what is now the US and Canada) adopted the Gregorian calendar in 1752. Because 1600 was a leap year in both calendars but the Julian calendar had a leap year in 1700 but the Gregorian calendar did not, this meant that "eleven" days needed to be skipped. Wednesday, September 2, 1752 was followed by Thursday, September 14, 1752.


title: Gregorian calendar

text: In the USSR, the October Revolution of 1917 was celebrated in November. In 1917 the Russian Empire still used the old Julian calendar. Changing the calendar meant 365 days after the revolution started was now in November 1918.


title: Gregorian calendar

text: In 1923 some Eastern Orthodox Churches changed to the Gregorian calendar. Christmas Day is the same as the Catholic and Protestant churches, but the date of Easter continues to be worked out differently.


title: Gregorian calendar

text: The Russian Orthodox Church, as well as some other Eastern Orthodox Churches such as Georgian and Serbian, did not want this change, so Russian Christmas Day is about two weeks after the rest of Europe.


title: Gregorian calendar

text: Japan adopted the Gregorian calendar's way of working out leap years on January 1, 1873, but the months have numbers instead of names. Japan also starts year one with each new reign, but uses reign names not the name an emperor might be best known by in the west. For example, the reign names "Meiji" year 1=1868, "Taisho" 1=1912, "Showa" (Emperor Hirohito) 1=1926, "Heisei" (Emperor Akihito) 1=1989, and so on. The "Western calendar" (西暦, "seireki") using western year numbers, is also widely accepted by civilians and to a lesser extent by government agencies.


title: Gregorian calendar

text: Some old dates in Britain were written and documented with two different years. This is because Britain did not start a new year until March 25, so for a few months it was one year in Britain and the next year in other countries.


title: Gregorian calendar

text: The letters OS (for "Old Style") and NS (for "New Style") were used to help determine the year being used. For example, King Charles I died on January 30, 1649. In "Old Style" it is correct to say that Charles I died "January 30, 1648 (OS)". Using "New Style", as we determine dates now, the correct date and year would be February 9, 1649.


title: Gregorian calendar

text: In the old calendar, the year started on March 25, this was the Quarter Day when rents and taxes fell due. This became April 5 which is why the tax year in the United Kingdom begins on April 6.


title: Gregorian calendar

text: People sometimes use the term N.S. or New Style to mean the Gregorian calendar, with Old Style (or O.S.) meaning the Julian calendar.


title: Carom billiards

text: Carom billiards, sometimes called carambole billiards or simply carambole (and sometimes used as another word for a game called "straight rail") are a family of billiards games played on cloth-covered tables. In these games, the players strike heavy balls with sticks called cues. Carom billiards tables have no or opening where balls are sunk, that snooker and pool tables do have. In its simplest form, the object of carom billiards games is to score points or "counts" by bouncing one's own ball, called a cue ball, off of the other two balls on the table. The date the first carom game was invented is not exactly known. Also, how exactly the games developed and which game was first is not clear. However, carom billiards games are believed to have started sometime in the 18th-century (the 1700s) in France in Europe.


title: Carom billiards

text: There are many different games, each with distinct rules, strategies and objects of play, that are all part of carom billiards. Some of the most well known games are "straight rail", "cushion caroms", "balkline", "three-cushion billiards" and "artistic billiards". There are many other carom billiards games that combine aspects of these games, but that are not as well known. For example, the "champion's game" was a short-lived game that developed during a transitional period between the invention of straight rail and the invention of balkline. Other games are combinations of these games and other games played on tables "with pockets" (pool or snooker games), such as "English billiards" played on a snooker table and its related games, "American four-ball billiards", and "cowboy pool", played on a pool table.


title: Carom billiards

text: The word "carom" means any strike and bounce off something. It started being used to describe the pocketless billiard games in the 1860s. It is a shortening of the word "carambola", used in Spanish and Portuguese and spelled "carambole" in French. Carambola was earlier used to describe just the red ball used in billiards games, but later was given to the game itself. Some people who study word origins suggest that "carambola" was originally the name of a yellow-to-orange colored, tropical Asian fruit, known in Portuguese as a "carambola". This was taken from an earlier word, "karambal", from the Marathi language of India, also known as starfruit. The accuracy of the fruit origin has been questioned. It has been said to be just a legend, because the fruit does not look very similar to the big red ball that is used in carom games, and there is no direct proof for the fruit explanation.


title: Carom billiards

text: Cloth has been used to cover billiards tables since the 15th century (1400s). In fact, the company that became the most famous maker of billiard cloth, Iwan Simonis, was formed in 1453. Most cloth made for carom billiards tables is a type of cloth called "baize" that is dyed green in color, and is made from 100% wool that has fibers that are made to be very straight (a process called worsting). Baize cloth provides a very fast surface allowing the balls to travel easily across the table material, called a "bed". The green color of cloth was originally chosen to look similar to grass. Green has been the common cloth color since the 16th century (1500s). However, the color also serves a useful function. Human eyes more easily see green than any other color. This allows players to keep playing for longer periods of time without straining their eyes.


title: Carom billiards

text: Modern billiard balls are made from "phenolic resin", which is a type of very strong plastic. The size of carom billiards balls is normally 61.5 mm (2⁄ in) in diameter. They weigh between 205 and 220 grams (7.23 – 7.75 ounces; 7.5 is average), and are quite a bit larger and heavier than the balls used for pool games. While UMB, the International Olympic Committee-recognized world carom billiards authority, permits balls as small as 61.0 mm (approximately 2⁄), no major manufacturer produces such balls any longer, and the main standard is 61.5 mm. The three standard balls in most carom billiards games are a completely white cue ball, a second cue ball sometimes having a red or black dot on it (to help people in telling the balls apart), and a third, red ball. In some sets of balls, however, the second cue ball is solid yellow. Both types of ball sets are allowed in tournament play.


title: Carom billiards

text: Billiard balls have been made from many different materials since the start of the game. For example, they have been made from clay, wood, ivory, plastics (including celluloid, Bakelite, crystalate, and phenolic resin) and even steel. The most common substance from 1627 until the early- to mid-twentieth century was ivory. The search for a substitute for ivory use was not for environmental reasons but based on how expensive they were and fear of danger for elephant hunters. The search was made more enticing when a New York billiard table maker offered a $10,000 prize for a substitute material. The first usable substitute was made from a material called "celluloid". Celluloid, which is an early form of plastic, was invented by a man named John Wesley Hyatt in 1868. There was a problem with the material though. Celluloid was unstable and highly flammable, sometimes exploding when people were making it.


title: Carom billiards

text: The stick used to hit billiard balls, called a billiards cue, is different in some ways from the typical pool cue. Compared with pool cues, billiard cues are often shorter, with a shorter end cap (called a ferrule), a fatter bottom portion where the back hand grips the stick (called a butt), a wooden screw in the middle rather than one of metal or plastic, and a smaller tip diameter. These features make the billiard cue stiffer. This stiffness helps players in striking the larger and heavier billiard balls as compared with pool balls. The stiffness also acts to reduce an effect called "deflection" (sometimes called "squirt"). Deflection is an undesirable effect from the use of sidespin. Sidespin is spin placed on a ball by striking it not at its center but off to one side of its center, causing it to spin as it travels down the table. Deflection causes a ball to travel not in a straight line in the direction it was struck.


title: Carom billiards

text: Underneath the cloth of billiard tables is a very hard rock called slate. The slate bed of a billiard table is often heated to about 5 °C/9 °F above room temperature, which helps to keep moisture out of the cloth to aid the balls rolling and rebounding in a consistent manner, and generally makes a table play faster. A heated table is required under international carom rules and is an important requirement for the games of three-cushion billiards and artistic billiards. Heating table beds is an old practice. Queen Victoria of England (1819–1901) had a billiard table that was heated using zinc tubes, At that time, though, the reason for the heating was different. The heat was used to keep ivory balls from going out of shape (warping). The first use of electric heating was for a tournament in the game of "18.2 balkline", that was held in December 1927 between two players: Welker Cochran and Jacob Schaefer, Jr. "The New York Times" announced it with fanfare: "For the first time in the history of world's championship balkline billiards a heated table will be used ..."


title: Carom billiards

text: Straight rail, sometimes called carom billiards, straight billiards, the three-ball game, the carambole game, and the free game in Europe, is thought to date to the 1700s. No exact time of origin is known though. It was called French caroms, French billiards or the French game in early times, taking those old names from the French who made the game popular. The object of straight rail is simple: one point, called a "count", is scored each time a player's cue ball makes contact with both object balls (the second cue ball and the third ball) on a single strike of the cue ball. Winning is achieved by reaching a certain number of points, agreed to between the players to be the winning number.


title: Carom billiards

text: When straight rail was first invented there was no restriction on the way points were scored. However, the technique of "crotching", meaning to have two balls right next to each other on the area of one of the table's four corners where the rails meet—the "crotch"—made scoring a lot easier. This resulted in an 1862 rule which allowed only three counts before at least one ball had to be sent away from the corner in order to legally score another point. Techniques continued to develop which increased counts greatly despite the crotching ban. One of these techniques is called "nursing", and made scoring much easier. A "nurse" is a series of shots where the balls are kept very close together, allowing a player to score off of them with very soft strokes without changing their positions much, so the scoring can continue. The most important of these nurse techniques, called the "rail nurse", involves nudging the balls down a rail, moving them just a few centimeters on each score and keeping them close together and positioned at the end of each stroke in the same or near the same arrangement so that the rail nurse can be repeated.


title: Carom billiards

text: Professional straight rail in the United States was only seen for six years, from 1873 to 1879. It was followed by a game designed to reduce the use of the rail nurse so that spectators would not be bored by watching it. Today, straight rail play is not very common in the U.S. but it still popular in Europe, where it is thought to be a good practice game for balkline and three-cushion billiards. Europe hosts professional competitions, known as "pentathlons" after the ancient Greek Olympic competitions, in which straight rail is one of five billiards games at which players compete. The other four are called 47.1 balkline, cushion caroms, 71.2 balkline and three-cushion billiards.