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Saturday, December 8, 2007

What is the largest freshwater fish in the world?

The Arapaima from South America is generally thought to be one of the largest freshwater fishes in the world. The biggest one found is said to have been 15 feet in length with a weight of over 400pounds. Most are between 7 and 8 feet long with a weight of 200 pounds, but even this is a colossal size for a fresh water fish.

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Friday, November 9, 2007

Spy Cameras

Different types of spy cameras

1. Wireless spy cameras
2. Night vision spy cameras
3. Hidden cameras to caught the thief
4. Motion activated spy cameras
5. Peep hole spy cameras

Wireless spy cameras are the most selling spy cameras in the world. It is very convenient due to lack of cables. We can place this spy cameras inside the shelf , on ceiling, inside the toys etc.

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Thursday, November 8, 2007

Who was the French Forest Ranger famous for his fables?

His name was Jean de la Fontaine. His father was the ranger of the forest of the duchy of Chateau-Thierry in champagne, Jean was born there July 8, 1621, and educated at first for the Church. He turned, however to the law but abandoned this on succeeding to his father’s ranger ship in 1647.

He married the same year but soon separated from his wife and he must have de3cided that forest ranging was not for him for its is known that form 1660 he lived in Paris. He began to write verses and translated some the minor classics.

In 1668 his first six books of animal fables were published. In wonderfully easy verse, they rate high among the glories of French Literature. In them Fontaine demonstrated a deep knowledge of nature, gained probably from the days when he roamed the forest Chateau-Thierry as a ranger.

A second series of fables appeared in 1679 and a third in 1693. They are today still read extensively throughout the world.

Jean de la Fontaine died in Paris April13, 1695.

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Why is the Moon not always completely round ?

The Sun always lights up half of the Moon’s surface the part facing the Sun. But, as the Moon moves around the Earth and the Earth moves around the Sun, different parts of the sunlit Moon are visible to us. Sometimes we see the whole of the sunlit surface, this is what we call the ‘full’ Moon. Sometime we see only the left or right part, which looks like as slice of melon. So we see the Moon in several stages. These are called phases of the Moon and are known as: full moon, warning Moon, new Moon and waxing Moon.

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Monday, November 5, 2007

Why are stars grouped in constellations?

People who gazed at the skies in ancient time’s believce4d that they could see the shapes of animals and peoples traced out in the stars. These star groups, or constellations, have the Latin names of the shapes and astronomers use the names in identifying stars. But the stars in a constellation do not belong to any actual group in space and may be far apart. The twelve constellations lying on the ecliptic, the sun’s path through the sky, are called the zodiac.

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Wednesday, October 31, 2007

What is a lightship?

A lightship is like a floating lighthouse. It anchors in one spot to warn shipping of such nearby dangers as sand banks or dangerous currents. At night it projects a powerful beam of light. The lamp is fitted in such a way that the beam stays steady, even if the ship is being tossed about by waves. Lightships also have their name painted on each side, so that during daylight hours ships can use them to check their own position.

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Thursday, October 25, 2007

What kinds of tools did early man use?


Some animals and birds make use of tools. There are some good examples among the birds. For example, the song thrush commonly feeds on snails which it opens by flying up with the shell in its bill and dropping the snail on convenient stone. The bird often uses the same stone on a number of occasions so that it may become littered with broken shells.
The stone is often referred to as a thrush’s anvil. The members of the shrike family often make use of thorns on which they impale their prey. But man more than any other animal has taken advantage of his large brain capacity to increase his power to hunt, kill, build his homes, and so on.
It is man’s ability to hold things in his hand with has enabled him to make such use of tools, where other animals have had to rely on their strength and agility, their teeth and their claws. Man’s first tools and weapons were stones which he had picked up. He chose stones that had been worn and sharpened by the weather into shapes that could be used as clubs or for cutting and scraping. As you might imagine the right shaped stones were not always easy to find, so that in time man learned to fashion primitive tools to a constant design that suited his purpose.
Many of the early men were carnivorous, that is, they fed largely on meat. This meant that a lot of the stones that have been positively identified as prehistoric implements were designed to kill animals, and then to scrape the flesh off the bones of the victim. Tools of prehistoric man could be made of bone, tooth, or more frequently stone, and in particular, flint. Flint was chosen because it breaks to give a flake with a very sharp, hard edge that could be used as, say, an axe. At first, these primitive weapons would be held directly in the hand. Eventually, however, man learned how to attach these axe-heads to a wooden shaft, and the power of the weapon was increased.
As he became more experience in making stone tools, the tools became more and more advanced in their design so that soon he was making blades, scrapers, and even arrowheads. Arrowheads were a great advance because they meant that for the first time man could kill his prey without putting himself to the risk of approaching what could be a very dangerous animal. Of course, these weapons could also be used to wound and kill other men.

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Tuesday, October 23, 2007

Are all deserts hot?


The definition of a desert is a place where the lack of moisture makes it impossible for anything but a few special life forms to grow. This applies not only to hot places, like the Sahara and the Gobi deserts, but also to very cold places too. Because all or most of the moisture there is turned to ice, almost nothing can grow there, which makes it a desert. So, you see, a great deal of the Artic is desert as well as the hot places people think of as being deserts.

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Monday, October 22, 2007

How are Clouds formed?

Clouds are formed when warm moist air rises into the sky. When it reaches a certain height, the warm air cools down and the water vapor in it condenses in to small drops of water, forming clouds. There are several different types of cloud. The ones which are highest are usually made up of drops of ice, and are the thinnest. These are called cirrostratus and cirrocumulus clouds. Lower clouds are called altostratus and altocumulus clouds. Lower still are the stratocumulus clouds and the nimbostratus clouds – these are the thick and shapeless rain clouds- and the lowest of all are the stratus clouds, which are seen as fog over high, mountains regions. Thunder clouds are called cumulus and cumulonimbus clouds, and these are the fat, cauliflower shaped ones.

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Friday, October 19, 2007

Is fresh air really fresh?

How many times have you heard someone say, ‘I think I’ will go out for a breath of fresh air”? Have you ever stopped to think what this means in our industrialized world? Of course, if you happen to be living high up among the mountains where there is little or no industry and few people your chances of finding fresh air are quite good. But what of the build-up areas of Britain and Europe or America? Even if you have not experienced it yourself, we expect you have heard of smog. This word is a mixture of the words ‘smoke’ and ‘fog’, which is very apt because smog really is smoky fog. London was once famed for its ‘pea-soupers’, that is, fog containing so much, sulfurous waste that it resembled the yellowish green color of pea soup and was almost as difficult to breathe and see through. These smogs usually occurred during the early months of winter when the fogs that would normally be present at that time of year became contaminated with all the smoke from cars and factory chimneys.

It is interesting to note how much influence pollution of the air, at first by smells of household waste and later by pollution, has influenced the distribution of people in cities like London. As you probably know, London has an ‘East end’ and ‘West end’ until quite recently the East end has been by far the poorer half of the city. This is because winds usually blow from west to east carrying the dirty air with them. People who could afford to choose where they wanted to live went to the western side leaving the smelly east for those with smaller incomes. In Los Angeles, in America, which is also famed for its smog’s, the prevailing winds are from east to west so that the London situation is reversed.

Today, many industrial countries have introduced ‘Clean Air Acts’ preventing the burning of ordinary coal in homes in certain areas and controlling the amount of smoke that factories can release. This means that some areas, such as London, Certainly have air containing much lees dust and dirt, and smogs are almost a thing of the past. In general, however, the air in our countries is far from fresh. The millions of cars on the road pour vast quantities of poisonous carbon monoxide gas into the atmosphere. It has even been suggested that if supersonic flight became popular, with the ‘planes flying at such hi8gh altitudes. The upper atmosphere could be affected in such a way as to permit deadly cosmic rays to reach the Earth.

The next time that you see some plants or trees next to a busy road, take a closer look at the leaves. You will probably find that they are covered with a film of black, oily dust. Remember that this is the same air that we are all breathing.

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Thursday, October 18, 2007

What are ores, and where might you expect to find them?

You must realize that the Earth provided us with all the raw materials swallowed up by our industries. Many of these materials are minerals. The word ‘mineral’ is used to denote any substance obtained by mining. It is clear that the words mine and mineral have similar origins. You might expect that minerals would be spread throughout the Earth, and indeed, this does happen. Occasionally, however, minerals may accumulate in sufficient quantities for man to be able to remove them comparatively easily. When this situation arises, the deposits are usually known as ores or ore bodies. The minerals associated with the ores that have no real economic value are usually referred to as gangue minerals, the consequent scarcity of them, and improved methods of mining and refining, material that was once thrown on the spoil heaps can now provide valuable sources.

Ores can occur in a variety of ways. With ores or iron, for example, the same ore can arise as a result of different methods of concentration. Many ores other than iron are formed in association with magma tic process. If you remember the way in which magma cools and forms crystals. It will come as no surprise to you to learn that metals such as chromium and nickel result from the settling into bands of the relevant crystals as the magma cools. There are often watery solution charged with minerals coming from magmas and these also provide supplies of metals such as mercury or copper. Both these minerals are in short supply, and in fact, deposits of mercury are almost completely confined to areas in Spain. Not all ores have been formed by igneous activity, however. Important deposits of iron in England have resulted from concentration by sedimentary process. Deposits known as placers are typical sedimentary ores. Of course, oil and coal must be considered as economic minerals and these have obviously resulted from sedimentation.

The sea may one day provide much of the world’s minerals. It has been known for some time that there is great richness of gold in the sea but as yet it has not been worthwhile nor even possible to exploit this mineral wealth. Even uncommon metals like vanadium, which is used for the nosecones of spacecraft, is concentrated in the blood of an unexciting sea animal – the sea cucumber.

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Wednesday, October 17, 2007

Where and what are the galaxies?


Our galaxy, vast island of stars though it is, is only one of millions of similar galaxies scattered throughout space as far away as we can see through our telescopes. The nearest galaxies to our galaxies are two small satellite galaxies called the Magellanic clouds. They can be seen only in the southern hemisphere, and look like pieces torn out of the Milky Way. A large nearby galaxy is the Andromeda galaxy, which can be seen with the naked eye as a faint patch. It is over 2 million light – years away.

Galaxies come in many shapes. Many are spiral. Elliptical galaxies look like globular clusters of stars, and irregular galaxies such as the Magellanic Clouds have no particular structure. About a hundred million galaxies can be seen with the largest telescopes. Galaxies, like stars, tend to form clusters and our galaxy is one of a cluster of over tweny7 that include the Andromeda Galaxy.

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Tuesday, October 16, 2007

Why is the time different in other countries?


The time it takes for the Earth to make one rotation has been divided into 24 parts, known as hours. This division was made to give us a fixed unit of time.

We take as a reference point the moment when the Sun is at its highest point in the sky (when the sun is at its highest point in the sky (when the shade is at its minimum).This is called mid-day, or noon.

However, this does not happen at the same moment on each part of the Earth because the Earth is turning all the time. Therefore, when it is mid-day in London it will be seven o’clock in the morning in some parts of the United States of America. Because the USA is such a large country, there are even time difference between some of the States.

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Monday, October 15, 2007

What is a rack railway?


Ordinary railway lines usually look as they are laid on level ground. In reality most stretches of railway track have a slight gradient, so that during a journey of any reasonable length, a train will be running up and down a number of very gradual slopes. However, there is a define limit to the degree of steepness a train can manage going up hill before its wheels start to skid on the tracks. In mountainous areas especially, it is not always possible to avoid gradients which a normal train simply could not climb, even by carrying the track through deep cuttings and tunnels. To overcome this difficulty rack railways have been built. Locomotives intended to run over such sections of track have a toothed, or cog, wheel fitted between the normal running wheels. This connects with third rail, also toothed, fitted to the track itself. This is the rack, its cog wheel engages the rack rail and so holds the train to the track with no risk of skidding.

Some rack railway lines pass through mountainous regions such as Alps. Other have been built to carry passengers to the actual summits of mountains, such as Snow-don in North Wales, and Mount Washington and pike’s peak in the United States.

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Sunday, October 14, 2007

Can trains run without rails?


For many years railway engineers have been thinking about new kinds of track for trains to run along. The parallel metal rail tracks with which we are familiar are not very efficient by modern standards. Because wheels are needed to move the trains along, a good deal of power is lost through friction in the moving parts. Ordinary railway tracks also set a limit to the speed that trains can go, especially round curves. They take up a lot of room, and they are expensive to build and keep in good repair.

Some trains, such as those operated on the Paris Metro, run very efficiently on rubber tyres. Other even more interesting advances in this field have been the experiments with monorail systems. Monorail means ‘one rail’, and several types of train have been designed which are suspended from an elevated monorail track. Spectacular results, in terms of speed and comfort, have been achieved.

Yet other trains have been built which sit astride a single metal or concrete track and slide along it. Called aero-trains, they have been designed to move like hovercraft. An even more advanced idea is to suspend a train from a monorail by magnetizing the rail. In all these cases there is hardly any friction to overcome, and much greater safety.

New forms of motive power are also being considered, including jet propulsion. The day may come when trains will be able to move almost as fast as aircraft

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Saturday, October 13, 2007

Why is the British flag called the ‘Union Jack’?


The Union Jack, the official flag of Britain since 1801, is really three separate flags in one, for it combines the English Cross of St.George, the Scottish cross of St Andrew and the Irish cross of St Patrick, England, Scotland and Ireland were originally Independent countries, and the Union Jack symbolizes the fact that they now from the United Kingdom, another name for Britain. Although generally known as the Union Jack, this is incorrect because it is the term for a flag flown only from the jack staff in the bows of a ship to indicate it is a man-of-war. Through popular use, however, the Union Jack gas become the accepted name for the flag.

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Friday, October 12, 2007

What is the origin of the Marathon race?

The Marathon is a long, grueling race which traditionally closes the Olympic events. It is taken from the amazing achievement of the Greek runner Pheidippides, who ran over twenty-six miles in for hours, taking news to Athens of the Persians’ defeat at the Battle of Marathon in 490 B.C.

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Thursday, October 11, 2007

Who are the Cossacks?

Many Hundreds of years ago, Russia was full of different tribes and races of people who had made their way from the great plains, or steppes, and mountain ranges of Asia. One of these races – the Cossacks – settled along the banks of the River Don which flows into the Sea of Azov, near the Black Sea. At the same time. They bred a special kind of horse which was noted for its great strength and stamina, and they became splendid horsemen. Their reputation as riders and warriors grew over the years, and they came to be looked upon as some of the finest cavalry soldiers in the world.

Sometimes the former Russian rulers, the tsars, used the Cossack cavalry to crush rebellions among the peasants. At other times the Cossacks were the pride of the Russian army, and could always be relied upon to strike fear into the hearts of the enemy. They were especially effective during Napoleon’s invasion of Russia in 1812, attacking his lines of communication and pursuing his armies during the terrible winter retreat. The German army also came to fear the Cossacks regiments during the Second World War.

Today the Cossacks are as famous as ever. They give exciting riding displays. They have also formed a choir which gives concerts all over the world.

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Tuesday, October 9, 2007

What is an electrocardiograph?


When a doctor takes a pulse he is felling the patient’s hear-beat. If the heart is beating faster than normal it may be a sign – like a rise in temperature – of illness somewhere in the body. For signs of illness in the heart itself a more careful check is usually needed.

The working of the heart is controlled by electrical impulses, and each part of its-the various valves where blood flows in a out – produces its own electrical wave pattern. By attaching electrical terminal points to the outside of the chest and connecting these to an electrocardiograph, these wave patterns can be observed. For when the electrocardiograph is switched on, an automatic device like pen moves up and down over a special sheet of graph paper, recording each wave impulse. This shows exactly the pattern of each complete heart beat. If anything is wrong with the heart, it will be shown by irregularities in these patterns. The pattern sheets or electrocardiograms can then be kept by doctors and compared over a period of time, which is extremely useful in the treatment of heart illness.

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How do astronauts ‘walk’ in space?


If an astronaut leaves his spacecraft during a journey, he cannot walk about in the ordinary way. There is nothing but empty space. There is not even any gravity to pull him in one particular direction. He can only guide himself by the same means as the spacecraft itself – by rocket propulsion. So when astronauts do leave their spacecraft during a flight – perhaps to help in docking operations with another spacecraft – they carry specially designed hand rockets with them. If they point the rocket exhaust in one direction, and give the engine a burst of power, they will move in the opposite direction. In this way they can steer themselves.

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Who found the Red Cross?

The Red Cross was found by a Swiss, Jean Henri Dunant, after he had witnessed the terrible plight of the wounded at the Battle of Solferino in 1859, Five years later, in 1864, the first Geneva convention was called to establish a code of conduct for nations at war, and Dunant obtained the convention’s agreement that both wounded soldiers and medical services should be treated as neutrals.

The flag chosen to represent the international medical service that grew out of dunant’s work was a red cross on a white background, this being the reverse colours of the Swiss flag. It also gave the organization its name. In Muslim countries, however, the flag is a red crescent on a white background, to distinguish it clearly from the Christian symbol of a crucifix.

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Monday, October 8, 2007

Where is the world’s oldest underground railway?

The first city to build an underground railway was London. Once the route was planned, a great trench was cut along the streets, the railway tracks were laid and the trench was covered over again, to restore the road and create a railway tunnel underneath. This method of tunnel making is called cut and cover.
The original route of the London Underground was nearly four miles long and ran from Paddington Station to Farringdon Street in the City of London It was opened 1863. The first trains were hauled by steam engines, and the smoke in the tunnels made the journey very unpleasant. But as the world’s first underground railway it was a cause of great excitement and regularly carried 30,000 passengers a day.
Further sections of steam operated underground railway soon followed. Then in 1890 the first really deep-tunnel or ‘tube’ railway was built in London. For this new tube railway, electric locomotives were built. The first trains they hauled had no windows, because windows were thought to be unnecessary if the train was only to travel through a tunnel deep under the ground. The train guard called out the name of each station as the train arrived at it.

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Saturday, October 6, 2007

Why some gardens are called ‘Botanical’ Gardens?


Private and public gardens and parks are created to make our surrounding more pleasant. The purpose of ‘botanical garden is to provide the right setting for making a scientific study of different kinds of plants. Botanical gardens contain greenhouses which enable exotic plants to be grown. There are also laboratories for study and experiments, and libraries.
Botanical gardens are usually open to the public, so we are given the opportunity to see plants which we wouldn’t normally see in our own country. One of the most famous is Kew Garden in England where you can seen a wide variety of plants and trees from many countries.

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Friday, October 5, 2007

How can we hear the sea in a shell?

Sad to say, it isn’t really the sea which you can hear when you hold a shell up to your ear, even though it may sound exactly like it. What is really happening is this… All sounds move through the air on vibrations of air called sound waves. We cannot see sound waves moving, but even the tiniest sounds being made in a room will have their own sound waves. There is air too, of course, in the spiral cavity inside the shell, and when sound waves enter they make this air vibrate as they bounce backwards and forwards off the inner wall of the shell. The result is a deep rumbling sound from the air which is resounding inside the shell. This sound reminds us of the sound of waves beating on a shore. It is in just the same way as this that air, vibrates inside the ‘resonator’, of musical instruments, making the sounds of the notes being played.

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Thursday, October 4, 2007

How is fog formed?

Water vapor is always around us in the atmosphere, in varying amounts according to pressure and temperature. When the temperature drops suddenly, these water vapor particles condense on the dust specks in the air, and this produces the haze we call ‘fog’.
‘Smog’ is a combination of smoke and fog. And is a particular menace in the industrial cities of America, but surprisingly it is Athens in Greece which suffers badly from smog. Smog eats away at the classical Greek building there, such as the Parthenon, at an amazing rate, causing serious damage.

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Wednesday, October 3, 2007

Why is the word love used in tennis?


Long ago, no score was indicated on French tennis scorecards by an egg-shaped zero. This was known as “I’oeuf”, the French word for egg, and the English-speaking players used the same word, but in this case it should like love, and has been called love ever since.

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Tuesday, October 2, 2007

Who Invented tennis?

The indoor game of ‘real’ tennis was played in the middle ages. During the 19th century it over flowed on to the lwn where players made up their own rules. In 1874 Major Walter Wing field invented rules for lawn tennis. Even by 1890, however, ‘real’ tennis rackets were still being used.

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Monday, October 1, 2007

What are the Olympic Games?


The Olympic Games is the biggest sporting event in the world. It takes place every four years, each time in a different country. Amateur sportsmen and women from over 100 nations take part. There are about 20 sports, of which the most important are track and field athletics.

The idea for these competitive events came from Ancient Greece. And the spirit of the games has always been one of true sportsmanship; that is, fair competition, without the aid of cheating in any form. However, competition is so fierce these days that it is hard for competitors to live up to these ideals.

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Sunday, September 30, 2007

Are there any animal-eating plants?

Yes, although they do not eat anything larger than insects (which, of course, are members of the animal kingdom).
These carnivorous plants capture plants their prey using various means. The pitcher plant has tubelike leaves that hold water, and insects crawl down in to these leaves only to be caught on tiny hairs which line the tube. They then slide down the tube into the water, where eventually they drown.
The sundew has circular leaves, this time covered with hairs on the outside. Each hair has a drop of sticky liquid at its tip which holds on to the insect and prevents its escape, while the leaf curls inwards and traps it, ready for eating
But perhaps the most well-known animal-eating plant is the aptly-named Venus’ fly-trap. This has hinged leaves, again with hairs over their surface When an insect lands on one of these especially sensitive hairs, the leaf closes up on its hinges, trapping the insect inside.

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Saturday, September 29, 2007

How does a magnet work?

When you bring a magnet close to another metal object such as a nail, the nail will be attracted towards it. This power of attraction is created by lines of force whi ch surround the magnet. They cannot be seen, but if you place a thin sheet of paper over a magnet, and scatter iron filing on the upper side of the paper, the filing will fall into place according to the lines of force. They will reveal what is known as a magnetic field.

Most of the filings on the paper will be attracted to the two ends of the magnet. These ends are the magnet’s poles. The earth itself is like a giant magnet, with its opposite ends at the North and South Poles. This is why the metal needle of compass will swing round until it is in line with the earth’s magnetic field and points towards the North Pole.

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Friday, September 28, 2007

How is Paper made?

Paper is made from wood, and many of the world’s paper mills are found in those countries which have great forests – Canada, Sweden and Finland.

The newly cut trees are usually stripped of their bark, branches and foliage where they have fallen, so that by the time they arrive at the paper mill they are ready for processing. The tree trunks are first cut into thin strips, mixed with water, and ground to a heavy, sticky pulp. This wood pulp is then cleaned of dirt and other impurities, and also chemically bleached to remove the original brownish colour of the wood. The Cleaned and bleached pulp next passes through special kinds of rollers which flatten it and draw it out until, at last, if beings to look like sheets of rather soggy paper. These sheets are finally dried and refined until the finished paper is produced.

High quality paper is further ‘coated’ with clay and other materials to give it a specially smooth, white surface.

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Thursday, September 27, 2007

How do our lungs work?

Our lungs are like two spongy bags. Just as a sponge can be filled with water and then squeezed dry again, so our lungs fill with air when we breathe in and then release most of the air again when we breathe out. As air enters the lungs it passes down a series of smaller and smaller tubes, which are known as the bronchial tubes, until it ends up in thousands to tiny air sacs. At this point oxygen from the air passes through the lining of the lung and into the blood. This oxygen is vital to the blood stream, as it helps to carry food energy to every other part of the body. Oxygen passes into the blood stream through the lungs, and so, in a similar way, waste products, such as carbon dioxide, pass out of the blood and are removed from the body as we breathe out again.

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Wednesday, September 26, 2007

How do we get rubber from trees?


Rubber comes from a tropical tree. The juice of the rubber tree, called latex, is extracted through slanting cuts is the bark. The juice drips into a container attached to the tree. It is then collected and made into rubber, which can be used for car tyres, boots etc.,

Another juice extracted from trees is maple syrup, it comes from the maple tree which is grown in North America. The Juice flows out of holes bored into the wood of the tree. Maple syrup is popular in the USA and is used on pancakes and ice cream

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Tuesday, September 25, 2007

How is coal made?

Coal is formed from the remains of trees and plants which grew millions of years ago. They delayed and sank into the ground, and were pressed under layers of rock and other minerals.
As this vegetation dried up, it turned into peat, then into coal. The Coal is found underground in layers called seams. Mines have to be make in order to dig it out. Coal is a very useful product. Not only is it used as fuel but also in the manufacture of such things as dyes and insecticides.

Major recoverable coal reserve is in USA and other large reserve are in Russia, Australia, China, India and south Africa. Highest coal producing contries are China, USA and India.Major coal exporters Australia, Indonesia and China.



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How did Chess Begin?

Chess is said to be the oldest game in the world, originating in India 5,000 years ago with the Buddhists, who believing war to be wrong, devised the game of chess as a peaceful substitute. From India the game spread to Persia, Arabia and then to Western Europe. The word ‘chess’ is derived from the Persian word ‘shah’ meaning king, and ‘check-mate’, from ‘shah mat’. The king is dead. At one time the king could be captured, which would be impossible in today’s game, and in ancient times the queen was the weakest piece on the board, only finding her present power 500 years ago. The method of ‘castling’ was introduced to the game 400 years ago and the rook got its name from the Indian word ‘ruhk’, meaning soldier.


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Sunday, September 23, 2007

First electric train

The world’s first electric train was designed by the German scientist Werner von Siemens. It was shown at an international trade exhibition in Berlin in 1879. A Special track was built for the train which hauled up to thirty visitors at time around the exhibition. One of earliest electric railways in England was Volk’s Electric Railway built along the sea-front at Brighton. This railway was opened in 1883.
It was a marvelous holiday attraction at that time, and is still very popular with visitors to the seaside town. The first Electric trains to be used as a serious means of transport appeared on the London Underground in 1890 and the building of Longer distance electric railway began after the First World war.

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Saturday, September 22, 2007

Why do the season Change?

We have summer and winter weather because of the way the earth spins around the sun on a tilted axis. The axis is what we call the line from the north Pole through the South Pole, and it tilts because of the combination of forces at work on the earth, from the pull of the sun and the moon.

This means that during part of the year the North Pole tilts nearer the sun, and at other times further away from the sun. When the Northern Hemisphere is turned to sun the countries north of the equator have their hot, summer weather, while the countries of the Southern Hemisphere, who are further from the sun at this point, have their winter weather.

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Friday, September 21, 2007

How credit cards work?

A credit card is a thin plastic card, usually 3-1/8 inches by 2-1/8 inches in size, will bear identification information and special number code. The services are credited to the particular persons account for credit and he or she has a grace period of repaying the credited amount without interest. After the grace period interest rates will take over. Today, the information on the card is read by automated teller machines (ATMs), store readers, restaurants, cruise ships ,bank and Internet.

Different types of credit card

There are different types of Credit cards available in the market according to your needs. There are credit cards allotted only for Gas stations. Most of the companies offer cards like gold, silver and platinum cards, each differs in their services. The higher grade cards have more money in credit and the grace period will be more. Before opt for a credit card make sure you read all the terms and conditions carefully, otherwise you will fall in to a trap of high interest rates.

Things to know before buying a credit card

Whatever card you choose you have the right to know about the following information's about the credit card.
The annual percentage rate (APR)
Credit issuer or company providing the credit line
Amount of the credit line
Length of the grace period
Annual fees, if applicable
Fees for credit insurance
In United states most of the people have at least one credit card. 35% have more than one. Even though there are a great number of credit card holders the number of internet buyers are not that much significant. The main reason of this is the increases number of stories about internet thieves who steal the credit card numbers through hacking. Now a days the websites offering internet buying are taking all measures to avoid internet hackers to get their client information.

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Credit card

Credit card is often called as the plastic money as it replaces money in the modern world. Most credit cards are often given if you produce a valid income certificate, bank statement, salary certificate or other legal documents claiming you are capable of repay the amount credited by you. The future of transaction will be credit card as it is convenient for both the payee and the seller. There are security issues concerning credit cards all over the world, but as the technology advances these issues will be tackled more seriously in the future. Most banks often credit card services now a days. All these credit cards are associated with major credit card companies like VISA, MasterCard, AMEX and Discovery. These credit cards are accepted worldwide and convenient for frequent travelers.

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Why is athletics good for you?

Athletics is a form of Physical education which carefully develops and exercises the different parts of the human body, and improves the athlete’s over all health, both in mind and in body. Athletics was practiced in ancient civilization, and classical Greece made athletics famous with their well-known Olympic Games and their High standards. Today, athletics is a discipline which has been scientifically developed, is recommended by doctors, and is practiced all over the world at local, national and international meetings.

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Thursday, September 20, 2007

Which Europeans first landed in Australia?

During the sixteenth century, the Portuguese were the principal traders in the East Indies. By 1600, however their place had been taken by the Dutch who, sailing via the Cape of Good Hope, set up a powerful base on the island of Batavia. Soon their ships were seeking new lands in order to open up more trade. In 1606 a Dutch ship called the Duyfken, ‘the Dove’, anchored off northern Australia and some of the crew went ashore – the first Europeans to do so. They were refilling their water casks when they were driven off by fierce natives. The Duyfken sailed away again without exploring any other part of the cast Australian continent.

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Wednesday, September 19, 2007

Vehicle tracking system.

Vehicle navigation system with satellite technology and interactive maps increased the security of modern luxury cars. Vehicle tracking systems works with the help of global positioning system (GPS) It can find the location of our vehicle anywhere in the world. A tracking software can locate the correct position of the car. Using this system we can protect our valuable cars from theft. This vehicle tracking system is available in car accessories selling shops. They will install it in the car.
For some vehicle tracking system there is a monthly service charge. Some cars have a factory fitted security system and they have one year free service offer.

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Who invented Photography and when?

There was no single ‘inventor’ of photography. It evolved through the combined work of of many people of many different nationalities.
One Frenchman, Joseph Nicephore Niepce (1765-1833), often gets the credit, however, since he was the first to obtain a picture ‘from nature’ with a camera, in the modern photographic sense. He was also the first to ‘fix’ a picture, so that it did not immediately deteriorate, though the result was still not as permanent as with a present-day ‘fixer’. A Plaque near the estate where Niepce used to live reads. “Dans ce village Nicephore Niepce invents la Photographie en1822”. Experts, having examined the metal plate used in this first Photograph, think 1826 is probably more accurate.
It was in 1839, when the painter Jacques Daguerre’s process was made public, that the subject of photography became known. Daguerre had modified Niepce’s work to produce his daguerreotype. It was recorded that “opticians’ shops were crowded with amateurs panting for daguerreotype apparatus, and everyone wanted to record the view from his window”.

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Tuesday, September 18, 2007

Who invented Gramophone - Record-Player?

First, Thomas Alva Edison invented the phonograph. The telephone had just been invented.
Edison realized that since it worked because of the vibrations in the diaphragm of the telephone mouthpiece when somebody talked into it, if some kind of stylus could be attached, then it could produce a pattern on something soft, so the sound could be recorded permanently. It should then be possible to play it back, using a similar stylus, and so reproduce the original sound.
His first phonograph used a cylinder of tin foil. A stylus, moved along it by a screw while the cylinder was turning, cut a sound into the till foil from a microphone. To make it play back, a hearing-tube with a stylus attached was used instead of the microphone.

That was in 1877, when Edison himself recited the nursery rhyme, Mary had a little lamb’ into his machine.

Over the next few years he improved his invention, eventually using waxed cylinders instead of tin foil.
The phonograph cut grooves as the stylus moved up and down.
The modern disc , where the stylus moves from side side instead, was invented by Emile Berliner and was first demonstrated in Philadelphia, USA in 1888. The first disc were made of vulcanized rubber.

Records made of shellac Records made of Shellac came in to being in 1897, the same year as the first disc recording studio was opened by the Berliner Gramophone Company.

By 1898 the Gramophone Company had opened in Britain and a factory which they owned opened in Hanover, Germany, to mass produce seven-inch records. Germany, to mass produce seven-inch records.

Paper labels appeared on records in 1900-the famous “His Master’s Voice” Picture was the first (now known as HMV).

The Decca Company manufactured the first portable (wind-up) gramophone in 1913, and the first disc to be recorded electrically instead of mechanically appeared in 1920. Electric gramophones or record-players came in 1925.

The first long-playing records (LPs) actually appeared in 1904, but those playing at 33 1/3 revolutions per minute, as now, were not produced until 1931.

Discs made of shellac broke easily, but these began to be replaced by discs made of almost unbreakable vinylite in 1946.

That led the way to LPs as we know them today, when Peter Gold mark developed the first ‘Microgroove ‘disc in 1948, with full production starting a year later. This marked the end starting a year later. This marked the end of the old ‘78s’ – records playing at 78 revolutions per minute.

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Who invented Ice-Cream?

Fruit Juices kept cold by being packed around with show were known to the Pharaohs of ancient Egypt - but these were ‘water-ices’ rather than proper ice-cream.
Something like ice-cream is known to have been served to King James II of England in 1686 at the price of $ 1 per portion, while in 1660 his elder brother, Charles II, is known to have eaten ice-cream in Paris while he was in exile.

It is also known that George Washington, the President of the USA, was keen on ice-cream in 1790.

Probably the ice-cream of that time was based on the discovery of Blasius Villefranca, living in Rome, who in 1550 found that freezing-point could be reached if saltpetre or salt were added to snow, and so managed to produce a creamy, frozen mixture.

Then in 1851, Jacob Fussell, a milk supplier of Baltimore, USA, found that cream was going to waste at certain times of the year.
He set himself up as a supplier of ice-cream to other milkmen, so establishing the world’s first ice-cream factory.
Such a factory was set up in London in 1870 for the benefit of a large number of Italian immigrants who had arrived about that time, who through selling ice-cream became known as ‘hokey-pokey’ men, so called because they used to shout in Italian “ecco un Poco’. which means “Here”s a bit.
The ice-cream corner was invented by accident in 1904, when in Louisiana, USA, the girl-friend of an ice-cream salesman rolled a wafer biscuit around her ice-cream to stop it dripping on to her clothes - so the story goes.
On the other hand, it is more likely that it was invented by an Italian immigrant to the USA, Italo Marcioni, in 1903.

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Monday, September 17, 2007

Who Invented the Match?

From earliest times, in all parts of the world, people have made fire by rubbing a hard stick against a soft stick so that soft flakes of wood, sloughed off by the hard stick, started to smoulder. Another way was to use flint, a very hard stone, striking it against a lump of iron to produce sparks.
Until the eighteenth century, the only improvement on these primitive methods was the tinder box, which contained a piece of steel, flint and some dry tinder for the sparks to ignite. Tinder was often pieces of charred linen or silk; sometimes even dried fungus. The Process of raising a spark could be very time-consuming, especially, if the tinder was cold and damp.
Matches were first invented as a method of transferring the file form the smouldering tiner to where it was needed. Splinters of pine were used, their ends dipped in sulphur, which flared easily and made dangerous fumes. It is thought that the Chinese used similar sulphur matches as long ago as the sixth century. For time sulphur matches were cheap and popular, but still the tinder box was needed to make the initial spark. All over Europe scientist were trying to do away with the need for the tinder box.
The first real breakthrough came in 1827 when English Chemist John Walker invented a match with all the fire-producing compounds in its head. He called them ‘friction lights’, because the flame was created by friction, and soon the idea was taken up by large manufacturers who made them in their millions

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Saturday, September 15, 2007

Who invented Laser?

A laser beam is an extremely intense narrow parallel beam of light. The word itself is derived from the words ‘light amplification by stimulated emission of radiation’.

Albert Einstein said in 1917 that it should be possible to make rays of light of the correct frequently be directed on an atom to make it release its energy in the form of light, but it was until 1958 that the right calculations were made by A.L. Schawlow and C.H. Townes to make this possible.
Schawlow and Townes’s first experiments failed, but by 1960 they had succeeded in generating the first laser beam, using a type of ruby.

Since then, the laser has been used in high-powered versions for cutting through metal, in delicate surgery such as in eye operations - and for putting on special effects at pop concerts and for street Christmas light displays!

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Friday, September 14, 2007

Who invented Christmas card?

Sir Henry Cole decided that he was too busy to write to all of his friends at Christmas. 1853, so he asked John Calcott Horsley, an artist, to design a card for him with a picture on the front.
One thousand were printed and what Cole did not need was sold by the printer at one shilling (5p) each.

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Thursday, September 13, 2007

Who invented Television?

There was not just one inventor of television. Experiments had been carried out in 1862 by the Abbe Caselli, an Italian priest living in France, who invented a system of transmitting pictures of handmade drawings and written messages.

In 1881 Shelford Bidwell, an Englishman, was able to demonstrate an early form of television which used a cell of selenium (a photoelectric cell) moving up and down mechanically in a box. But he thought that the only way to produce a good picture was to make use of 90,000 photoelectric cells, each attached by a separate wire - and that was beyond him.

A Scottish electrical engineer, Alan Campbell-Swinton, hearing of Bidwell’s experiments and knowing that Ferdinanad Braun, of Austria, had invented the Cathode ray Oscilloscope (rather like a modern television tube, but designed for showing electrical waves), put the two ideas together.
He realised that an electronic switch was needed to switch on the photoelectric cells in turn, and that the oscilloscope tube could be used to receive pictures.

He also designed a camera to go with it, which stored the light falling on to the photoelectric cells so that when it was switched on all the variations of light were transmitted at the same time.
That was in 1911, and became the basis of the television system which went into operation by the BBC at Alexandra Palace, London, in 1936.

Meanwhile, in Russia, Boris Rosing had invented his own television apparatus in 1907 which did not work very well. But one of Rosing’s students, Vladimir Zworykin, left Russia for America in 1919, and invented his camera tube which used Campbell-Swinton’s storage of light principle in 1923. His first pictures were still not very good, but by 1928 he had improved the system considerably.
John Logie Baird, working in London, gave his demonstration of ‘real’television in 1926. This was the first proper television picture ever transmitted, but baird was using a mechanical system instead of an electrical one (although he developed an electronic receiver later).

The race was then on between the RCA Company, of America and Marconi-EMI of England, to develop television. The Marconi-EMI team, under Issac Schoenberg, solved the final problems with the invention of the Emitron camera in 1934.

Meanwhile, John Baird was still working on his television system. In 1928 he produced the first television picture in color rather than in black and white, the high-definition color television picture in 1938, and in 1941 the large screen color television receiver. Unfortunately, he always refused to accept that electronic transmission of pictures was essential, rather than mechanical methods, so none of his inventions are now present in modern television sets.

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Who Invented Chocolate?

Chocolate – made from cacao seeds – for eating (as distinct from drinking which appeared somewhere in the 17th Century) had been known in France and Italy, but the first bars of chocolate were made in a factory set up by Francois – Louis Cailler at Vevey, Switzerland, in 1819.
In 1826 Fry’s of England, were producing Chocolate lozenges’ for medicinal purposes. In 1842 John Cadbury, of Birmingham, started to sell ‘French eating chocolate’ by the slab. Fry’s introduced their chocolate cream stick in 1853.
The first box of chocolates was made by Cadbury’s in 1866, and the first milk chocolate was manufacturing by Daniel Peter, Cailler’s son-in-law, in 1873.

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Wednesday, September 12, 2007

Who Invented Chewing –gum?

Chewing-gum was first made by John Curtis, of Bangor, Maine, USA, in 1848, on his kitchen stove. He started production in a factory in Portland, Maine, with a variety of different gums in 1850.
Modern chewing –gum, however, owes its origins to an American photographer called Thomas Adams.
He tried experimenting with a tree substance called chicle as a substitute for rubber in the production of moulded goods, but the experiments were not successful.
One day he chewed a lump of chicle and suddenly thought of adding flavouring and selling it as gum.
In 1872 he opened a small factory. Business expanded rapidly aided by the fact that the Tutti-Frutti Company began selling it from machines (the first were erected on platforms of the Newyork Elevated Railroad in 1888)
Chewing-gum introduced to Britain in 1894, but failed to catch on. Then the firm of Wrigley reintroduced it in 1911, and it probably became successful for a similar reason as in America - sweet -shops refused to sell it, so it appeared on the streets first in vending machines.

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Tuesday, September 11, 2007

Who Invented Carbon Paper?

The quite simple idea for making an exact copy (carbon copy) of what is being written on it a second sheet
Sheet underneath was invented by Ralph Wedgwood, of London, in 1806.
To make the first carbon paper, he soaked thin paper in ink, and then dried it out between sheets of blotting – paper. After that he placed the paper on which he wanted to write on top.
Placing, the dried ink in between did the rest.

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Monday, September 10, 2007

Who invented Balloon?

The two types of Balloon, hot-air and gas-filled, were invented in the same year, 1783.
Brothers Joseph and Etienne Montgolfier, Paper-makers near Lyons, France, noticed that when their kitchen fire was alight, bits floated up the Chimney in the currents of hot air. So they experimented with paper bags. In June, 1782, they made a bag out of cloth lined with paper. It was 35.5 metres(110ft.) in circumference. In a public square they set this up, lit a fire under-neath, and the balloon floated off for a mile and a half before landing.
In Paris, a Physicist, J.A.C.Charles, heard of what had happened in Lyons, but did not know how it had been done, Hydrogen had only recently been discovered, so in August he sent up a smaller balloon which he filled with hydrogen (by pouring sulphuric acid over iron filings).
Then in September the Montgolfier brothers arrived in Paris with a huge hot-air balloon and sent up some animals in it while the king and queen of France watched. It was on 21st November, 1783 that the first balloon to carry people (two of them) traveled safely for more than 8 kilometers (5miles) in 25 minutes.

J.A.C. Charles watched with interest, realizing that his was a different type altogether, and on 1st December
Flew his balloon, (very much like a modern gas balloon, even to the value in the top to allow gas to escape
So that it can land), also with two people on board. His balloon flew for 27 miles before landing.

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Saturday, September 8, 2007

Who invented Ambulance?

The ambulance dates from 1792, Baron Larrey, Napoleon’s personal doctor, was worried about the way in which wounded men were being carried from a battlefield., They were simply put into an open cart and taken away , being jolted all the time over the rough ground.
Baron Larrey took a cart, had special springs mounted into it to make them more comfortable, and then had a cover erected over the top to protect the patients from the weather.
The invention proved to be a success. So in 1796 a special French Army unit was established to remove the wounded from battlefields, equipped with 12 of these ‘one-horse flying ambulances’.
It took more than 80 years before anyone thought that civilians might need ambulances, too. The first was used on the streets of Margate, Kent, in 1878 –pulled by hand, and with just one wheel! However, in 1883 one appeared with four wheels, rubber tires and was pulled by a horse.
The first ambulance to have its own engine – fitted with a Daimler engine – was demonstrated in Paris in 1895, but did not go into use with the French Army until 1900. In the same year France was to see the first civilian motorized ambulance appear.

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Who invented Computer?

Charles Babbage, of London, spent from 1823 to 1871 working on his ‘analytical machine’, designed to take instructions from punched cards, calculate with the aid of a memory bank, and print out a solution.
Unfortunately, despite all his efforts, the very precise engineering work needed to make the machine a complete success was impossible at the time.
Herman Hollerith, of New york. USA, who worked for the US Census Bureau, devised a machine in 1889 which used punched cards to store the information needed for the census, and so halved the time it took to work things out. He left the Census Bureau in 1896 to form the Tabulated Machine Company to manufacture the equipment which he had invented – and that later became part of IBM(International Business Machine).
The first electronic computer was the Electronic Numerical Integrator and Computer (known as ‘ENIAC’), Developed for the US Army ordnance in 1946.
Unfortunately, it weighed 30 tons and used 18,000 radio valves! Further, the machine got so hot while it was working that it could be sued only for short period of time.
Only after the transistor had been invented was the modern electronic computer possible, and the first to be produced was by Remington Rand in America and Ferranti in Britain, simultaneously in 1951.

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Friday, September 7, 2007

Who invented Diesel Engine?

The engine is named after Dr.Rudolf Diesel, of Germany, who produced his first engine in 1893.
In fact it is a compression-ignition engine. The mixture of air and oil inside a cylinder is compressed by a piston. This is increases the temperature to the point where the oil ignites, the explosion blows the piston back, then the process begins all over again. It does not use petrol but cheaper, heavier oil, and is a much more efficient engine regarding the use of fuel than a petrol engine.
The first engine of this kind to be manufactured, however, was one invented by Herbert Ackroyd-Stuart in 1890 and made by Hornsby & Sons, of Grantham, Lincolnshire, in 1892. The problem with this one was that in order to start it from cold extra heat had to be supplied to the cylinder head, and then removed after the engine was running properly. Hornsby’s did produce another version of the Ackroyd engine in 1892 which required no extra heat to start it – and in fact this was actually more like the modern diesel than the one which Dr Rudolf Diesel produced a year later.
Diesel, however, continued to develop his engine over the next four years, while Hornsby’s developed theirs no further, until he sold the rights in 1897. Diesel committed suicide in 1913, because of his serious financial problems.

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Who invented Electric Blanket?

An American, named S.I. Russell, invented an electric heating pad in 1912 to warm patients suffering from tuberculosis (wasting disease affecting various parts of the body) who had to sleep out of doors.
In 1926 the British Ex-Service Mental Welfare Society Started manufacturing a heated pad invented in Germany, which later became the Thermega under blanket. In America 1937 saw the ideas of a heated over-blanket became popular in Britain at about the same time.

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Who invented Escalator?

A ‘moving staircase’ was invented by Jesse Reno, of New York, USA in 1892, and it was first used on a pier at Coney Island, an American amusement park, in 1896.
It was a conveyor belt made up of wooden slats and driven by an electric motor. It was called the Reno Inclined Elevator. His had flat steps, like modern ones.
This was improved in its design by Charles See Berger in 1898 (because the original escalator was never actually built), and the Otis Elevator Company at once saw its potential use and began manufacturing it from 1899 onwards.

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Inventions, science, useful topics for students.