Guericke, Otto


German engineer who invented the first air pump and used it to study vacuum. In a famous experiment he placed two copper bowls of 14 inches diameter together to form a hollow sphere. After he removed the air from the sphere, horses were unable to pull the bowls apart, even tough they were held together only by air around them. In 1663 Guericke invented the first electric generator, which produced electricity by applying friction against a revolving ball pof sulphur.

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