SIBIEL, Alexander, known as FRAY DOMINGO, German antiquary, born in Saarlouis in 1709; died in Dessau in 1791. He studied at Mechlin, became a Jesuit, and was sent to New Spain in 1734. After being for several years a professor in the college of the order in Mexico, he was appointed vicar of a remote parish in the northern part of the country, where he discovered some half-buried monuments of the Aztec architecture covered with hieroglyphs. He devoted several years to their study, buying, meanwhile, Aztec antiquities whenever he could find them, and at last was enabled to read part of the inscriptions. Distinguished men of science, like Ventura and Boturini, had previously labored vainly for years to decipher Aztec inscriptions. Toward 1770 Sibiel returned to Germany and was appointed chaplain at the court of Anhalt. His works include "De arte Hierogliphum Mexicanormn" (Dessau, 1782); "Reisen in Mexico" (2 vols., 1785) ; and "Litterae annuae Societatis Jesu in provincia Mexicana" (5 vols., 1787).