in] of the New Physies. 63 



a soldier. Of his early days little or nothing is known, but he 

 himself tells us that he studied mathematics at Rome under 

 Benedetto Castello. His great ability was not only at once 

 obvious to his teacher but soon became known to others ; for 

 while as yet a young man, probably about 1640 or possibly 

 earlier, he was invited to and accepted the chair. of mathematics 

 at the University of Messina, which was then making itself felt 

 as an active seat of learning. He, like other mathematicians 

 of the time, was a pupil of Galileo, in the sense that he had 

 learnt much from that great man through his writings and 

 indirectly in other ways. But he had apparently never listened 

 to his voice, and so earnestly did he desire to do so that with 

 the consent and indeed at the expense of the University he left 

 Messina for a while in order to visit Florence and see Galileo. 

 Unhappily very soon after his arrival in 1642 Galileo died, and 

 Borelli, though he appears to have stayed some time in Florence 

 enjoying intercourse with Torricelli, returned to Messina, where 

 in 1649 he published his first work, an account of the pestilence 

 raging in Sicily in 1647-8. Though in the first place a 

 mathematician and a physicist, he like other learned men of 

 the time busied himself with inquiries reaching outside his 

 own line; that he was justified in doing so is shewn by 

 the fact that in this treatise he attacked the views held of 

 physicians concerning the cause of the disease, and contended 

 that it was due to what we should now call an air-borne 

 germ. 



His fame while at Messina grew so great and spread so far 

 that in 1656 he was invited by Ferdinand Duke of Tuscany to 

 fill the chair of mathematics in the University of Pisa. The 

 efforts of the Medici to make their university an academic 

 power were being crowned with success, and Pisa was now 

 outshining Padua. Borelli accepted the invitation, and so 

 began what was perhaps the brightest and the best part of 

 his career, though he was already forty-eight years old. 



Much as he owed to his chief teacher Castello, Borelli was 

 to a large extent a self-taught man. He seems not to have 

 paid much attention to literary studies, and his life at Messina 

 was probably more or less a provincial life, a life marked with 



