PICARD, JEAN, an eminent French astronomer, was born at Fleche in 1620, and became priest and prior of Rillé in Anjou. His knowledge of astronomy early attracted notice. On the 25th of August 1645 he was employed, along with Gassendi, in observing the solar eclipse; in 1653 he was appointed to the astronomical chair in the College of France; and in 1666 he was selected by Colbert to assist in founding the Academy of Sciences. Picard, however, was destined to become still better known for his improvements in practical geometry. In 1667, along with Auzout, he was the first to apply a telescope to the quadrant in the measurement of angles. It was his good fortune, shortly afterwards, to introduce the modern method of determining the right ascension of the stars by employing a pendulum to note the instant of their meridional passages. He brought this list of improvements to a close in 1669, by making the first exact measurement of a degree of the meridian. So great indeed were his services to science, that by the time of his death in 1682 he was worthy of being considered the father of French astronomy. The principal works of Picard are La Mesure de la Terre, Paris, 1671; Voyage d'Uranibourg, Paris, 1680; Observations Astronomiques faites en divers Endroits du Royaume; Observations faites à Bâle, Bordeaux, et Royan pendant l'Année 1680; and La Connaissance des Temps. There are also several contributions by him in the sixth and seventh volumes of the Memoirs of the Academy of Sciences. (See Delambre's Histoire de l'Astronomie, and his article "Jean Picard" in the Biographie Universelle.)