Санта-Мария-дельи-Анджели-э-деи-Мартири
After graduating, Gabriele went to Rome at the end of 1702, where he became librarian to Cardinal Pietro Ottoboni, a historian, antiquarian and astronomer. He helped Ottoboni build a sundial at Santa Maria degli Angeli e dei Martiri and helped in the work of reforming the Gregorian calendar. He continued to study mathematics, including differential and integral calculus and logarithmic curves. In 1707 he returned to Bologna where he published his best known work on first-order differential equations.