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The earliest form of air transport was balloons, which are sometimes called “free balloons” because they are forced to drift by the wind flow without any engine. This fact alone makes balloons not reliable enough for carrying people. If they were safer they would be used more for transportation, but at present the scientists use the balloons mostly for obtaining information about upper atmosphere, its density and other scientific subjects. Weather balloons are particularly used by meteorologists. They carry instruments whose readings are automatically sent back to the ground by the radio. The position of the balloon is obtained by radar.
The first balloons were done by Montgolfier brothers in the 18-th century.
Etienne and Joseph Montgolfier lived in a little village in France where their father had a paper factory. The two brothers took paper bags from their father, filled them with smoke over a fire and watched them go up into the air.
After numerous experiments they were ready to show how their balloons worked. On the day of the flight people from different places came to the little village to see the spectacle. The brothers had constructed a bag some thirty feet in diameter. That big bag was held over a fire. When it was in the air for ten minutes and then as the air bag became cold the balloon went down.
The news about the experiment reached the king who wanted to see it himself. So on September 19, 1783 Montgolfier brothers repeated their experiment in the presence of the King and Queen of France. This time the balloon carried a cage with a sheep, a cock and a duck who were thus the first air travellers. The flight was successful. The balloon came down some distance off with the sheep, the cock and the duck unharmed.
If the animals could live through this men could risk too. A month later a balloon was sent up with a Frenchman, Rozier by name. He stayed up in the air for twenty-five minutes at a height of about one hundred feet above the ground, and then came down saying that he had greatly enjoyed the view of the country.
A month later he and Arlandes made the first free balloon flight. Their friends who came to say good-bye to them were very sad as if the two men were going to certain death, but they went up several hundred feet, were carried by the wind over Paris and came down in safety.
In 1785 a Frenchman and an American crossed the English Channel in a balloon. When they had covered three quarters of the way the balloon began to go down. They threw everything they could overboard. If they had not done it, they would have never reached the French coast.
Comprehension Check
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