The Geometer has the special privilege to carry out, by abstraction, all constructions by means of the intellect. Who, then, would wish to prevent me from freely considering figures hanging on a balance imagined to be at an infinite distance beyond the confines of the world?

] and having studied Ptolemy and seen almost everything of Tycho Brahe Kepler and Longomontanus finally forced by the many congruences came to adhere to Copernicus and was a Galileian in profession and sect". Barometer
Torricelli's chief invention was the mercury barometer which arose from solving a practical problem.

Evangelista Torricelli (Italian: [evandʒeˈlista torriˈtʃɛlli] [About this sound] pronunciation (help·info)) was an Italian physicist and mathematician best known for his invention of the barometer.