Otto von Guericke

Otto von Guericke (1602-86), German physicist, born in Magdeburg. He studied law at the universities of Leipzig and Jena and mathematics at the Leiden University. After hearing of the experiments of the French scientist Blaise Pascal and the Italian scientists Galileo and Evangelista Torricelli in connection with atmospheric pressure, he began to work on the properties of air and the creation of a vacuum. In the course of these experiments he invented the first air pump in 1650. In 1654 he carried out before the Imperial Diet at Regensburg the famous demonstration of the Magdeburg hemispheres. Two hollow bronze hemispheres were fitted together, and with a pump the air was removed from the resulting sphere. Two eight-horse teams could not pull the halves apart; when the air was readmitted, the hemispheres fell apart. Similar evacuated hemispheres are used today in laboratory demonstrations of atmospheric pressure.

Von Guericke investigated fields of natural science other than pneumatics. In 1672 he developed the first machine for producing an electric charge. In astronomy he worked on predicting the periodic return of comets.