Otto Von Guericke

Born Nov. 20, 1602, in Magdeburg; died May 11, 1686, in Hamburg. German physicist. Mayor of Magdeburg from 1646.

In trying to prove the existence of the vacuum, Guericke invented the air pump in 1650. In a series of experiments he proved the existence of air pressure (the experiment with the “Magdeburg hemispheres”), determined the elasticity of air, its ponderability, its ability to support combustion and to conduct sound, and the presence in it of water vapor. Guericke created one of the first electrical machines, a rotating sulfur sphere polished by hand, and discovered the phenomenon of electrical repulsion as well as electrical luminescence. In 1660 he was the first to build a water barometer and use it to predict the weather.