First French edition of Physices Elementa Mathematica, Experimentis Confirmata by the famous Leyden professor Willem Jacob van 's Gravesande (1688-1741). It was translated from the Latin after the third enlarged edition of 1742 by the author's pupil and friend Elias de Joncourt (1700-1770), teacher of mathematics at 's-Hertogenbosch. 's Gravesande was the earliest influential exponent of Newtonian philosophy in continental Europe, and his present major work, representing the largest, best argumented and most philosophical summary of Newtonian science and experimental method, was widely read not only in Europe but in England as well. 's Gravesande had become aquainted with the English Newtonian philosophers when he was sent as secretary to the Dutch embassy Wassenaar van Duyvenvoorde early in 1715 to congratulate George I on his accession to the English throne. He stayed in England for a year. He was present at the demonstration at the Royal Society of experiments by J.T. Desaguliers in March 1715, and became himself a fellow of the Royal Society in June. In 1717 's Gravesande was called to Leyden as professor of mathematics and astronomy. Twenty years later he attracted hundreds of foreign students to the Leyden university, together with his colleague Herman Boerhaave, and in 1736 Voltaire made a special journey to Leyden to secure 's Gravesande's appraisal of his Élémens de la philosophie de Newton. Afterwards Voltaire wrote a warm appreciation of 's Gravesande's kindness and learning. For his experiments to try and determine the laws of nature and the properties of bodies, 's Gravesande designed many new instruments, which are also depicted on the engraved plates. The numerous plates, much enlarged for the present French edition.