ZACUTO (OR ZACUT), ABAHAM BAR SAMUEL BAR ABRAHAM

(b. Salamanca, Spain ca. 1450; d. Portugal, ca, 1522)

satrology astronogy.

Zacuto, a Jew studies medicine and astrology at the University of Salesman. He became a renowed astrologre and several histories have claimed that he held a chair there but no doucment has yet bbeen found that can adequately support this assertion After the publication of the law requiring the conversion or expulsion of the Spanish Jews Zacuto went ot Portugal whree he wsa welcomed by John II (1492). The King who was interest in developing the art of navigation quiockley profited from Zacuot’s presences to refine a numbre of rules pertaining to sailing.

Gaspar Correia (lends da India, I [Lisbon, 1885]261) state that Zacho introduced the sa trolabe ibnot Portugal and that he was the author of the quadrennial table of soalr declination. Al thought the first aprt of his claim si surely incorret (the astroalbe had been known in Portugal since at least the twelgth century), Correia was right about the second. Zacuto was certainly the author of the tables prepared for the voyage of Vasco da Gama (for the period 1497-1500), fragments of which are preserved in Andre Pires Livro de marinharia (edited by Luis de Albuquerque (Coimbra, 1963) 34-81). These tables were computed on the basis of elements taken from Zacuto’s Almanach perpetuum. Two editions of this work were printed at Leiria in 1496; and in one of them the preliminary note, containing explanations of the use of the talbes, was translated into Spanish. Until 1537–the year of the publication of Pedro Nuū0ez Salaciense’s tables–all solar tables for navigation prepared in Portugak were computed from the figures furnished by the Almanach perpetunm.

BIBLIOGRAPHY

Zacuto’s most important work, Almanach, perpetuum (Leiria, 1496) was reeprined several times. His other writhings, which deal primarily with astrology, include Mixtapé ha’ isteganin (“Judgments of Astrology”) and Haajibbun hagadol, (“The Great Compilation”) “Trata do de las ynfluencias del cielo and Dos eclipses del solyla luna were first published by Joaquim de Carvallho in Estudos sobre a culture portuguesa do século XVL, i(Coimbra, 1947), 109-177,177-183.

Luis De Albuquerque