FRISI, PAOLO (1728-1784), Italian mathematician and astronomer, was born at Milan and educated at the Barnabite monastery there and at Padua. He made his reputation by his Disquisitio mathematica in causam physicam figurae et magni tudinis terrae (1751), and became professor of philosophy in the College of Casale, and subsequently in the Barnabite college of St. Alexander at Milan. He was professor of mathematics at Pisa (1756-64) and in the palatine schools at Milan (1764-77), where he obtained papal release from ecclesiastical jurisdiction and au thority to become a secular priest. In 1777 he became director of a school of architecture at Milan. He had a European reputation as a consulting authority on hydraulics, and through him lightning conductors were introduced into Italy.
His other works include:—Saggio della morale filosofia (Lugano, 17J3) ; Nova electricitatis theoria (1755) ; Dissertatio de motu diurno terrae (Pisa, 1758) ; Dissertationes variae (Lucca, 1759, 1761) ; Del modo di regolare i fiumi e i torrenti (Lucca, 1762) ; Cosmographia physica et mathematica (1774, 1775 his chief work) ; Dell' architettura, statica e idraulica 0777); and other treatises.