CASTELLI, BENEDETTO. - Benedictine mathematician and philosopher, born in Brescia in 1577, died in Rome in 1644. He was one of Galilei’s best disciples, with whom he also collaborated in astronomical research. He taught mathematics at the University of Pisa. He devoted himself to the study of physics and gave particular attention to the study of running waters. On the movement of fluids and currents he wrote the work: Della misura delle acque correnti, published in Rome in the years 1628-39. To this study he added the Demostrazioni geometriche della misura, etc., studies which he dedicated to Pope Urbano VIII, who had previously consulted him concerning rather complex hydraulic works.
C.’s activity, however, did not remain confined within the scope of these disciplines: he left us several philosophical treatises, published under the care of Cardinal Leopoldo dei Medici. Though not particularly distinguished in style and fluency of expression, these treatises are essentially valuable for their content of intense passion: the defense of his master; indeed, few have felt such profound affection for Galilei. Also known is C.’s Discorso sopra la calamita, which A. Favaro published in Boncompagni’s Bullettino (16 [1883], p. 545).