Torricelli's barometric experiment of 1644.
© Science Museum / Science & Society Picture Library
Torricelli's barometric experiment of 1644. Diorama. Evangelista Torricelli (1608-1647), the Italian mathematician and physicist, is best remembered for the invention of the mercury barometer. Torricelli succeeded Galileo (1564- 12642) as mathematician to the court of Tuscany where he engaged eagerly in scientific activity. The experiment pictured is a particularly famous one in which the existence of atmospheric presure is experimentally demonstrated.