‎"LAGRANGE, (JOSEPH LOUIS). - THE INTRODUCTION OF THE 'GRAVITATIONAL POTENTIAL' THE PRIZE-WINNING MEMOIR.‎
‎Prix D'Astronomie Physique sur L'èquation séculaire de la Lune.‎

‎(Paris, Imprimerie Royale, 1776). 4to. Extracts from ""Mémoires de Mathematique et de Physique, Présentés à l'Academie des Sciences par divers Savans"", Année 1773. Pp. 1-61. A faint dampstain to right margin of the first leaves, otherwise fine and clean.‎

Reference : 44971

‎First printing of this importent memoir as it represents THE EARLIEST INTRODUCTION OF THE IDEA OF THE POTENTIAL, the ""Gravitational Potential"". The potential of a body at any point is the sum of the mass of every element of the body when divided by its distance from the point. Lagrange showed that if the potential of a body at an external point were known, the attraction in any direction could be at once found.""For the prize of 1774, the Academy asked whether it were possible to explain the secular equation of the moon by the attraction of all the celestial bodies, or by the effect of the nonsphericity of the earth and of the moon. Lagrange, who was equal to the scope of the subject, felt very stale and at the end of August 1773 withdrew from the contest. At d’Alembert’s request Condorcet persuaded him to persevere. He was granted an extension and thanked the jury for this favor in February 1774. He took the prize with ""Sur l’équation séculaire de la lune."" (DSB).Parkinson ""Breakthroughs"", 1773 P. ‎