In 1903, at Kitty Hawk in the United States, Orville Wright made what is said to be the first controlled powered flight of a heavier-than-air craft. People had already flown small airships, but there was now a race to make the first successful aeroplane. The Wright brothers and other would-be pilots had already built several gliders. The Wright biplane looked like a huge box kite, with a home-made engine that drove two propellers by means of chains – but it flew and it was controllable.
Clement Adler, in France, had flown under power in 1890 in a bat-shaped aeroplane powered by a steam engine. However, the aircraft was not controllable; so many people do not accept his attempt as the first flight.
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Alexander Graham Bell (1847-1922) was born in Scotland but moved to the USA. He realized that sound consists of vibrations, and he began working out a way of changing these vibrations into electrical impulses. These impulses could then be carried along a wire – this was the origin of the telephone. His rival, Thomas Edison, soon produced a much improved version of Bell’s telephone. Bell retaliated by devising a better version of Edison’s own phonograph.
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Wednesday, August 29. 2018
Although he was actually a draper, the Dutchman Antonie van Leeuwenhoek (1632-1723) ground glass lenses and used them to examine the world about him. In the 1670s he made his first crude microscope with a tiny lens, and this allowed him to be the first person to see microscopic life such as bacteria, yeast and living blood cells. During his career, van Leeuwenhoek ground a total of 419 lenses, and his microscopes became progressively more effective.
