With a brain capable of such remarkable exercises as the above-written vision, living his life in an atmosphere of books, and with all games and relaxations dear to boys of his age denied to him, it was no marvel that Jerome should make an early literary essay on his own account. The death of a young kinsman, Niccolo Cardano,[33] suggested to him a theme which he elaborated in a tract called _De immortalitate paranda_, a work which perished unlamented by its author, and a little later he wrote a treatise on the calculation of the distances between the various heavenly bodies.[34] But he put his mathematical skill to other and more sinister uses than this; for, having gained practical experience at the gaming-tables, he combined this experience with his knowledge of the properties of numbers, and wrote a tract on games of chance. Afterwards he amplified this into his book, _Liber de Ludo Aleae_. With this equipment and discipline Jerome went to Pavia in 1520. He found lodging in the house of Giovanni Ambrogio Targio, and until the end of his twenty-first year he spent all his time between Pavia and Milan. By this date he had made sufficiently good use of his time to let the world see of what metal he was formed, for in the year following he had advanced far enough in learning to dispute in public, to teach Euclid in the Gymnasium, and to take occasional classes in Dialectics and Elementary Philosophy. At the end of his twenty-second year the country was convulsed by the wars between the Spaniards and the French under Lautrec, which ended in the expulsion of the last-named and the establishment of the Imperial power in Milan. Another result of the war, more germane to this history, was the closing of the University of Pavia through lack of funds. In consequence of this calamity Jerome remained some time in Milan, and during these months he worked hard at mathematics; but he was not destined to return to Pavia as a student. The schools there remained some long time in confusion, so in 1524 he went with his father's consent to Padua. In the autumn of that same year he was summoned back to Milan to find Fazio in the grip of his dying illness. "Whereupon he, careful of my weal rather than his own, bade me return to Padua at once, being well pleased to hear that I had taken at the Venetian College the Baccalaureat of Arts.[35] After my return to Padua, letters were brought to me which told me that he had died on the ninth day after he had refused nourishment. He died on the twenty-eighth of August, having last eaten on Sunday the twentieth of the month. Towards the close of my twenty-fourth year I was chosen Rector of the Academy at Padua,[36] and at the end of the next was made Doctor of Medicine. For the first-named office I came out the victor by one vote, the suffrages having to be cast a second time; and for the Doctorate of Medicine my name had already twice come forth from the ballot with