17th Century vacuum experiment. 167MB2 Dutch engraving of the German scientist Otto von Guericke (160MB2-1686MB) experimenting with vacuums. Von Guericke was a German scientist, inventor, and politician, best known for establishing the physics of vacuums. Here, he is experimenting with Magdeburg - a pair of large copper hemispheres, with mating rims that were used to demonstrate the power of atmospheric pressure. When the rims were sealed with grease and the air was pumped out, the sphere contained a vacuum and could not be pulled apart by teams of horses. Image from 'Experimenta nova Magdeburgica de vacuo spatio', by Otto von Guericke, 167MB2.