(b. 13 April 1728; d. Milan, 22 November 1784)
mathematics, physics, astronomy.
Frisi was a member of the Barnabite order. In physics his research must be evaluated in relation to the concepts dominant in his time, which led him to justify and interpret certain phenomena of light and aspects of electricity, referring to the vibratory motion of ether and other properties attributed to it.
As an astronomer he concerned himself with the daily movement of the earth (in De motu diurno terrae, awarded a prize by the Berlin Academy), the obliquity of the ecliptic, the movement of the moon, the determination of the meridian circle, and matters concerning gravity in relation to Newton’s general theories.
His mathematical activity included studies on kinematics (composition of rotatory movements, etc.) and, notably, on isoperimetry. He also did work in hydraulics and was called upon to plan works for the regulation of rivers and canals in various parts of northern Italy. He was responsible for laying out the canal built in 1819 between Milan and Pavia.
Frisi wrote critical notes in, honor of Galieo, Cavaliers, Newton, and d’Alembert, illustrating the contributions each had made to science and the influence each had exerted. In Italy during his lifetime he was considered a scientific authority and was also well known abroad, so much so that his major works (which he wrote in Latin) were translated into French and English. Algebra e geometria analitica (1782) Meccancia (1783), and Cosmografia (1785), in which he brought together the best of his work, were, for that era, very up-to-date. Frisi was an editor of Il caffè, a newspaper that was influenced by the thought of the French Illuminati and that exerted a notable influence on the cultural, social, and political life of Milan in the second half of the eighteenth century.
I. Original Works. Among Frisi’s works are Disquisitio mathematica in causam physicam figurae (Milan, 1751); De methodo fluxionum geometricarum (Milan, 1753); Nova electricitas theoria (Milan, 1755); De Motu diurno terrae dissertatio (Pisa, 1756); Piano de’ lavori da Tarsi per liberare (Lucca. 1761); Del modo di regolare i fiumi, e i torrenti (Lucca, 1762); De gravitate universali corporum (Milan, 1768); Danielis Melandri et Paulli Frisii alterius ad alterum de theoria lunae commentaria (Parma, 1769); Opuscoli filosofici (Milan, 1781); Opera, 3 vols. (Milan, 1782–1785); and Operte seclte (Milan, 1825).
His many papers include “Dell’equilibrio delle cupole e delle volte,” in Alli della societa patriotica di Milano, 1 (1773), 222 ff.; and “Dissertatio de quantitatibus maximis et minimis isoperimetricis,” in Atti dell Accademia dei fisiocritici di Siena, 6 (1781), 121 ff.
II. Secondary Liteature. On Frisi and his work, see Girolamo Boceardo in Nuova Encilopedia italisana (Turin, 1875–1888), IX, 1005–1006; Francesco Jacquier, Elogio accademico (Vebice, 1786); Pietro Riccardi, Biblioteca matematica italiana dall’origine della stampe ... (Modena, 1870; 7th ed., 1928); and pecro Veri, Memorie appartenenti alla vita ed agli studi del sig. D. Paolo Fristi (Milan, 1784), which is reprinted in Operette scelie.