Petau (Lat. Petavius), Denis, a French chro-nologist, born in Orleans, Aug. 21, 1583, died in Paris, Dec. 11, 1652. He was trained from childhood to speak Greek and Latin, besides acquiring Hebrew and Arabic. In 1602 he obtained in a competitive examination a chair of theology in the university of Bourges. In 1605 he entered the novitiate of the society of Jesus at Nancy, renewed afterward his course of philosophy and theology in the Jesuit university of Pont-a-Mousson, taught rhetoric successively at Rheims, La Fleche, and Paris, and from 1621 to 1644 he was professor of dogmatic theology in the Sorbonne. Besides several volumes of discourses and poems, and editions of Themistius and Epiphanius, he published Opus de Doctrina Temporum (2 vols, fol., Paris, 1627); Tabula Chronological (fol., 1628); Uranologion (fol., 1630; 2d ed. by Hardouin, 3 vols., Antwerp, 1703); and Ea-tionarium Temporum in XIII Libris (2 vols., Paris, 1633-4; several times reedited and corrected by the author, and translated into French and English). His great theological work is Theologica Dogmata (6 vols, fol., Paris, 1644-'50; best ed., 7 vols, fol., Venice, 1758; last ed., 8 vols., Paris, 1865-'7).