Helium was discovered by British scientist named sir Norman lockyer in 1868. While studying the sun through a spectroscope. He noticed a mysterious line appearing in the spectrum. This was attributed to a new element, which did not Exist on earth it was called helium from the word Helios meaning sun in the Greek.

Many years later scientist discovered the presence of helium in our atmosphere its amount was so less that in 250,000cubic feet of air 1 cubic feet of helium existed. Helium is very useful element because of it lightness it is used in army and navy blimps, weather balloons. In certain parts of Texas, New Mexico and Kansas natural gas wells exist for obtaining helium.
Galileo was the first to notice the rings around the planet Saturn. They extended for about 170,000 miles. The middle ring is the brightest. It is separated from the outer ring by a dark space. The inner ring is very dim as far as is known, the ring are not made of continuous mass of solid or liquid mater.
They are composed of tiny, separate pieces of matter, but when seen from the earth they seem to be joined because of the way the ring are inclined we first see their northern side and then their southern side.

Dogs, cats and other mammals are colour blind. They cannot tell one colour from another. Their sense of smell is so advanced that they can differentiate between objects by their sense of smell.

So the long hairs of the cat's whiskers are what it depends on to know where it is, what there when the other sense organs cannot provide that information. But cats do have keen senses. Their hearing and sense of smell are highly developed. They have eyes that are directed towards this allows the cat to focus both eyes on the same subject at the same time and to focus its distance.

The cats eyes are also adapted to seeing in the dark during the day the pupil contract to slits, but at night they open wide to let in every bit of light of possible.

A fog is a cloud contact with the ground. When a cloud is near or on the surface of the earth it is simply called fog. The most common fogs are those seen at night and in the early morning over the lowlands and small bodies of water they are caused by a cold current of air from above striking down upon the warmer surface of the cold current of the land or water.
In the autumn they are very common, because the air is cooling faster day by day than the land or the water. As the earth cools at night the lower air gets cooler. Fog forms when this cool air meets the warm air just above. City fogs because of the pollution, are much thicker than the country fog.
Julius Caesar
Julius Caesar was the first government official record to order a traffic control regulation.

He passed a law that no woman was it drive a chariot in Rome.
Later, when the automobile was invented, the first traffic controllers were foot patrolmen, who directed the traffic by their hand. Then they were given hand-operated traffic lights. It was not until the early 1920s that automatic traffic lights were first used.

In 1927, it was improvised to adjust to the amount of traffic passing through the intersection at a given time. One of these lights, invented by Harry Haugh of Yale University, was first installed in New Haven, in April 1928.
John Ericsson
John Ericsson (1803-1889) was born in Sweden, the son of a mining engineer. He was educated largely along engineering lines.

When he was 17, he joined the army where his designs and maps soon become famous. Among his inventions were an instruments for taking sea soundings, a tubular steam boiler that saved steamship fuel, and a self-acting gun lock that made it possible to discharge naval cannon at any elevation despite the rolling of the ship.

In 1836 Ericsson invented the screw propeller, which was used by the first steamships in regular trans-Atlantic service.


The 24-hour day is based on the ancient Egyptian style, which was divided by day and night. They made shadow these shadow clocks or sundials had 12 periods of time to divide the day and they were the first timepieces.

The next kind of timepieces developed used fire and water. A candle with notches cut in the sides will measures time as it burns from notch to notch. Or a dish with a small hole in the bottom can be set on water. After a certain periods of time the floating dish will fill with water and sink.

The hourglass was developed about 2,000 years ago. Two hollow containers were connected so that could flow from one to the other. The top container was filled with enough sand to flow through the hole in one hour.

Elephants have an enormously heavy body, which may weigh about 5 tonnes. That is why their legs are short shaped like stout pillars.

The two ivory tusks that protrude from the upper jaw of an elephant are actually overgrown teeth. These tusks are used to dig up roots for food, used as weapons for defence. In the case of Indian elephants only the males have tusks.

The elephant's trunk is an extension of the nose and upper lip. It serves the elephant as hand, arm, nose and lips. It contains a great number of muscles, probably as many as 40,000. As a result, it is very strong and flexible. Because of this great strength, the elephant can use its trunk very effectively.
Clouds can sometimes stop making rain. The saturated cloud which contains water droplets, when meets a mass of warm air, evaporate. This is due to the warm temperature, which makes the droplet in the cloud evaporate before it can reach the earth as rain.

However, if the air beneath a cloud is moist, the droplets get bigger and condensation takes place. Pretty soon, each tiny droplet, become a drop and falls down as rain.
Bartolome Murillo

Bartolome Murillo was a painter with a difference. He was more interested in the people he used as subjects than the intricacies of his paintings. This is why his paintings are regarded as sentimental.

Born in Serville, Spain, he became an orphan at the age of 10. Later he went to Madrid where he was trained by the great painter, Diego Velazquez. In 1645, he returned to Seville and made it his home for the rest of his life.
Murille was a prolific painter. He painted mostly for churches and convents.

He also painted groups of beggars and peasants realistically. His hallmark was his excellent use of silver and golden colours which brought a touch of radiance to his paintings.

The earliest painters were cavemen. Paintings of animals were discovered which were a dated back to 30,000 to 10,000 B.C. in southern France and Spain. Many of these coloured drawings are amazingly well preserved since the caves were sealed up for many centuries.

The cave artist filled the walls with drawings in rich bright colours. Some of the most beautiful paintings are in the cave of Lascaux in France. The pigments used by the cave painters were earth ochers (iron oxides varying in colour from light yellow to deep orange) and manganese.

These were crushed into a fine powder, mixed with grease, and put on with some sort of brush. It made the paint fluid and the pigment's particles stick together. The cavemen must have made brushes out of animal hair or plants.

Comet Tails

As a comet approaches the sun, a tail usually appears behind it. It consists of very thin gases and fine particles of matter that are shot off from the comet's nucleus when it comes under the influence of the sun.
Comet tails are very different in shape and size.

Some are short and stubby. Others are long and slender. They are usually at least 5 million miles in length. Sometimes they are almost 100 million miles long! Some comets have no tails at all.

As the tail grows, the comet gains in speed because it is nearing the sun, moving towards its headfirst. Then a curious thing happens. When the comet goes away from the sun, it goes tail first with the head following. This is because the pressure of light from the sun drives off the very small particles from the comet's head to form its tail, always in a direction away from the sun.

Fleas are terrific jumpers. They have the extraordinary capacity to jump 7 to 8 inches into the air and 12 inches forwards. This is equivalent to humans jumping 450feet into the air and 700 feet forward. Fleas are parasites which lives on dogs and cats by sucking their bloods.. They have a small round head with mouthparts which are adapted to sucking. They have a tiny body with no wings and three pairs of legs.

There are hundred of species of fleas. In the US alone there are 50 different kinds of fleas. Fleas also infest rat s, squirrels, tame and wild birds, and nearly all other warm-blooded animals. During the middle ages flea infested rats spread bubonic plague. After infesting on the rat, the infected flea jumped on the humans thus spreading the dreaded disease.
Air Pressure

Differences in pressure may exist in a small region around you, and you will have a local wind blowing. If you live near the shore, you have and example of this every day. During the day, the land become heated, the air above it rises, and cool winds come in from the water to takes its place. At night, the water, and the breeze blows out from the land to take place of the rising warm air.
What is true in your immediate neighbourhood is true on a much larger scale of the winds that blow over the Earth. The warmest place on Earth is around the equator. So there is always a belt of warm air rising from this region.


No one really knows when or where the secret of making glass was first learned, though we know it has been used since very early days. The chief ingredients for making glass are sand, soda ash or potash and lime, melted together at a high temperature. Since these materials are found in abundance in many parts of the world, the secret of glassmaking could have been discovered in many countries.

According to one story, the ancient phoencians deserve the credits for this discovery. A crew of a ship landed at the mouth of a river in Syria. When they were ready to cook their dinner, they could find to stones on which to support their kettle. So they used lumps of niter (a sodium compound) from the ship's cargo.

Most of the changes that take place on the surfaces of the Earth after an earthquakes are seen along this fault line. The part of the fault line where the vibration is felt most strongly is called the "epicenter " of the earthquake. And if this is near a city, the destruction may be very great. The loss of life is usually due to failing buildings and fires that may be started by broken gas mains under streets.

The single region of the earth that has the most frequent earthquakes is Japan. There is an earthquakes there almost every day of the year. Of course, most of these are very minor quakes and do no damage at all. Another region that has frequent earthquakes is the Mediterranean area.
The earthquakes regions of the earth and area of recent volcanic activity are roughly the same. This is because both of these are regions where the earth's crust is not at rest.

If the earth were not rotating, winds would be north winds or south winds. But the spinning of the earth makes winds in the Northern Hemisphere deflect to the right and in the southern Hemisphere to the left.
The winds blowing towards the equator are called "the trade winds." Those blowing towards the poles are called "the westerlies." The US is largely in the zone of the westerlies.

There are other "prevailing" or common winds in other parts of the world. But as you can see, the wind does come from somewhere-and it comes from there because of very definite rezones caused by the way the air over the earth is heated

Some kinds of mosquitoes carry germs that cause disease, such as yellow fever, malaria and sleeping sickness. The germs that cause the disease are picked up by the mosquito and the passed on to another person it bites.

Typhus us a disease carried by the body louse. It is a serious danger whenever people must live in crowded conditions. Flies play a part in the spread of such disease as cholera, dysentery, hepatisis and typhoid fever. These diseases, like all those that are spread of carried by insects, are les apt to occur if and area is kept free of dirt- and if the insects are prevented form breeding.
The beds of rock salt that are formed in various parts of the world were all originally formed by the evaporation of seawater millions of yea ago. Since it is necessary for about nine-tenths of the volume of the sea water to evaporates for rock salt to the formed, it is believed that the thick rock-sale beds that are found were deposited in what used to be partly enclosed seas.

These evaporated faster than fresh water entered them, and the rock-salt deposits were thus formed.

Most commercial salt to obtained from rock salt. The usual method is to drill wells down to the sale beds. Pure water is pumped down through a pipe. The water dissolves the salt and it is forced through another pipe up to the surfaces

The legendary metal gold occurs in nature most exclusively in native state. First found by chance, it was being mined by 3000 BC and was being chemically extracted from crushed quartz (by amalgamation with mercury) by 1000B, or hammering into shapes and is resistant to corrosion and to chemical attack.
The conventional test for gold is to drop hydrochloric or nitric acid separately onto the metal; pure gold resists either acid alone but dissolves in a mixture of the two, known as aqua regia.

In amnesia by forgetting his anxiety, a man also forgets a great many other things, even including his identity. He may still act in a normal manner, but be unable to recall anything about the past.
He acts so normally that the may move about without attracting notice. Or he may wander restlessly from place to place. Or he may assume a new identity. Then he may suddenly recover his memory.
Where this doesn't happen, psychiatric help may enables him to do it. When he does regain his memory, he may not recall events that took place during his period of amnesia.

Chewing Gum
Chewing Gum is made of a gum base, sugar, corn syrup and flavouring. The gum base us what keeps it chewy for hours. For preparing the gum base un the factory, the materials are sterlised in a steam cooker and pumped through a centrifuge. This machine spins at high speed and throws out bits of bark and dirt found in the raw gums.

The clean melted gum base us mixed with sugar, corn syrup and flavouring. The mixture usually contains 20% gum base, 63% sugar, 16% corn syrup, and about1% flavouring oils. Some of the more popular oils are spearmint, peppermint, clove and cinnamon.

While this mass is still warm, it is run between a pair of rollers. It is thinned down into a long ribbon. Powder on both sides prevents the gum from sticking.
The blood that flows through the arteries, capillaries and veins of your body contains many different materials and cells. Each part of the blood has its own special work and importance.

There is, first of all, the liquid part of the blood. This is called the plasma, and it makes up a little more than half the blood. It is light yellow and a little thicker than the water because many substances are dissolved in it.

The red cells (also called red blood corpuscles) give the blood its colour. There are so many of them in the blood that it all looks red. There are about 35 trillion of these tiny, round, flat discs moving around in your body all at once. And they stay in the blood vessels at all times.
The reason we say "God bless you" after someone sneezes cannot be traced to any single origin, but seems to be connected with ancient beliefs. The Romans thought a person, expelled evil sprits when he sneezed, so everyone present would say "Good luck to you" after a sneeze, hoping the effort to expel the spirit would succeed.

Primitive people believed that sneezing was a sign of approaching death. When anyone sneezed, therefore, people said "God help you" because the person sneezed was in danger.

During the sixth century there was a plague in Italy, and Pope Gregory the Great offered that prayers be said against sneezing. It was at this time that the custom of saying, "god bless you" to persons who sneezed become established
Superstitions about lucky and unlucky days are just as common as those about numbers, and Friday probably has more than any of them centering about it. In ancient Rome, the sixth day of the week was dedicated to Venus. When the northern nations adopted the Roman method of designating days, they named the sixth day after Frigg or freya, which was their nearest equivalent to Venus, and hence the name Friday.

The Norsemen actually considered Friday the luckiest day of the week, but the Christians regarded it as the unluckiest. One reason for this is that Christ was crucified on a Friday.
Humphrey Davy
Humphrey Davy (1778-1829) was born in Cornwall, England, the son of a wood carver. Davy was educated to be a Doctor, but he soon turned to chemistry, one of his first outstanding discoveries was that of nitrous oxide, or laughing gas, which was used as an anaesthetic by surgeons and dentists. He was made a professor of chemistry in the Royal Institution of London when he was 21. His greatest invention was the Davy safety lamp, a small oil-burning lamp covered with a cylinder of wire gauze the absorbed the heat of the flame. It was in 1815. It reduced the danger of fires in mines.

The moon circles the Earth in an orbit that takes about one month to complete. It also spins, or rotates, on its axis, and it takes 27 days, 7 hours, and 43 minutes to make one rotation. Because the orbit and the rotation takes about the same amount of time, the moon always keeps the same side facing the earth.
The moon does not shine with its won light the way the sun does. It only seems to shine, because it reflects the sun's light. As the moon travels around the Earth, different parts of its are lighted up by the sun.
Sometimes you see the whole visible face of the moon lighted up, and at other times you see only a part of the moon's face lighted up. This is what makes the moon look as though it were changing shape in the sky.

Annie Johnston

Children's books writer Annie Johnston published her first book Big Brother in1893. The Little School, her most popular book, was published in 1895 and made into a movie in 1935. It is the story of a little southern girl with the lively temper of her old grandfather, a colonel in the confederate Army.

The Little Colonel was the first of 12 books about the adventures of his little girl. Johnston made her heroine like a girl she had met when visiting the peewee valley, near Louisville. Because she liked the peewee valley so much, Johnston moved there in 1898. It was her home until she died.Three years later Ericsson went to the US and in 1848 became a naturalized American citizen. His life in America was given over to many engineering projects. One of the most important was the construction of iron warships built with their machinery below the water and hence out of the reach of shot.

His most famous ship of this type, the Monitor, was built for the North in the "war between the states". It fought the confederate Merrimac in the first battle between ironclad ships.

There are two important characteristics that set mammals apart from all other animals. They are the only animals that posses true hair, or fur. And they are the only animals that produce milk. The word "mammal" comes from the Latin word "mamma", which means "breast". All female mammals nurse their young with milk that comes from glands, usually called breasts, on their bodies.
Mammals have certain other characteristics. The mammal's lungs and heart are separated from its stomach and intestinal tract by a wall of muscles called the diaphragm. The mammal's lower jaw consists of a single bone on each side. And-most important of all- mammals brains are much more highly developed than the brains of any other animals.
Koh-i-noor, the famed diamond set in the crown of Elizabeth the Queen Mother, has had a chequered history. It is an Indian stone found in Kollur, on the banks of the river Krishna in Andhra pradesh in 34 BC. It was discovered by a miner who, though he tried to hide it in a wound he made in his thigh, was found out and put to death.

Originally a lumpy Mughal-cut stone that lacked fire and weighed 191 carats, it was recut to enhance its fire and brilliance to a109-carat, shallow, oval brilliant in 1852 at Garrods of London, with different results.

According to some experts, Sultan Ala-ud-Din Khilji is credited with having taken the jewel in1304 from the Raja of Malwa whose family had owned it for many generations.

Some historians have identified it with the diamond given to the son of Babur, the founder of Mughal dynasty, by the Raja of Gwalior after the battle of Panipat in 1526, still others contend that it was presented to the Mughal Emperor Shah Jahan in 1656. Some claim that the stone was cut from the Great Mughal diamond described by the Great French jewel trader Jewan.