Used with
permission of Maiken Naylor, University at Buffalo, Buffalo, NY, USA,
http://ublib.buffalo.edu/libraries/units/sel/exhibits/stamps
Evangelista Torricelli (1608-1647), the Italian physicist and mathematician, is famous for his discovery of the principle of the barometer. He was Galileo's assistant until the latter's death. The unit Torr (1/760 of a standard atmosphere) bears his name.