In 1677 he graduated in medicine and surgery at the University of Pisa and in 1681 was appointed as naval surgeon by Cosimo III.

He embarked on a Tuscan galley for the Balearic Islands and went to Constantinople in 1683 with the florentine surgeon Pier Francesco Pasquali to tend to Musaipp Pasha Mustafa II, the son of the sultan Mehmed IV, after a serious fall from his horse.

From there they spent some time in Albania and Adrianople, and Tilli went on to Tunis, to study the remains of Carthage and to collect botanical specimens.

Carl Linnaeus praised Pisa's botanical garden as one of the finest in Europe.

[2] Cosimo III was an enthusiastic supporter of the garden, arranging for the importation of plants from as far afield as the Americas.