Grandlus, Gumo

, a philosopher and mathematician, was born Oct. 1, 1671, at Cremona, where his father, a branch of a decayed family, carried on the business of ai> embroiderer. His mother, a woman of considerable talents, taught him Latin, and gave him some taste for poetry. Being disposed to a studious life, he cliose the profession of theology, that he might freely indulge his inclination. He entered into the religious order of Camaldolitesj at Raverrna, in 1687, where he was distinguished for his proficiency in the different branches of literature and science, but was much dissatisfied with the Peripatetic philosophy of the schools. He had not been here long before he established an academy of students of his own age, which he called the Certanti, in opposition to another juvenile society called the Concordi. To his philosophical studies he added those of the belles lettres, music, and history. It appears to have been his early ambition to introduce a new system in education, and with that view he obtained the professorship of philosophy at Florence, by the influence of father Caramelli, although not without some opposition from the adherents to the old opinions. He now applied himself to the introduction of the Cartesian philosophy, while, at the same time, he became zealously attached to mathematical studies. The works of the great Torricelli, of our countryman Wallis, and of other celebrated mathematicians, were his favourite companions, and the objects of his familiar intercourse. His first publication was a treatise to resolve the problems of Viviani on the construction of arcs, entitled “Geometrica Demonstnuio Vivianeorum problematum,Florence, 1609, 4to. He dedicated this work to the grand duke. | Cosmo Til. who appointed the author professor of philosophy in the university of Pisa. From this time Grandius pursued the higher branches of mathematics with the stmost ardour, and had the honour of ranking the ablest mathematicians among his friends and correspondents. Of the number may be named the illustrious Newton, Leibnitz, and Bernoulli. His next publications were, “Geometrica dernonslratio theorematum Hugenianorum circa logisticam, seu Logarithmicam lineatn,1701, 4to, and “Quadratura circuii et hyperbola3 per infinitas hyperbolas et parabolas geometrice exhibita,Pisa, 1703, 8vo. He then published “Sejani et Rufini dialogus de Laderchiana historia S. Petri Damiani,Paris, 1705, awd “Dissertationes Camaldu lenses,” embracing inquiries into the history of the Camaldolites, both which gave so much offence to the community, that he was deposed from the dignity of abbot of St. Michael at Pisa; but the grand duke immediately appointed him his professor of mathematics in the university. He now resolved some curious and difficult problems for the improvement of acoustics, which had been presented to the royal society in Dublin, and having accomplished his objecvt, he transmitted the solutions, by means of the British minister at the court of Florence, to the Royal Society at London. This was published under the title of “Disquisitio geometrica in systema sonorum D. Narcissi (Marsh) archiepiscopi Armachani,” in 1709, when he was chosen a fellow of the royal society. This was followed by his principal work, “De infinitis infinitorum, et infinite parvorum ordinibus disquisitio geometrica,Pisa, 1710, 4to, and by many other works enumerated by his biographer, few of which appear in the catalogues of the public libraries in this country. Among other subjects he defended Galileo’s doctrine respecting the earth’s motion, and obtained a complete victory over those who opposed it. He was deeply versed in subjects of political economy; and various disputes were referred to his decision respecting the rights of fishery, &c. He was appointed commissioner from the grand duke and the court of Rome jointly, to settle some differences between the inhabitants of Ferrara and Bologna, concerning the works necessary to preserve their territories from the ravages of inundation. For these and other important public services, he was liberally rewarded by his employers. He died at the age of sevejity-two, in July 1742. 1

1 Moreri.- —Fabroni Vita Italorum.