Capillarity before Laplace: Clairaut, Segner, Monge, Young

Abstract

The first half of Laplace's theory of capillarity [1] was published several months after the publication of Thomas Young's Essay on the Cohesion of Fluids [2]. When, after a delay caused by the war, it finally reached England, Young naturally was upset by the emergence of a formidable rival. He could have admitted the superiority of the new doctrine and used his leisure to develop the latter, but he did not choose this alternative; presumably, his insufficient knowledge of the calculus was a factor in his decision. He preferred to attack Laplace, and, as so often happens, the offensive was two-pronged: many of Laplace's results were declared to be erroneous, and the correct findings were said to be not new. In a recent paper [3], I have discussed one of the former criticisms and shown it to be unjustified. Here I review the work of four of Laplace's predecessors, and I attempt to estimate the extent to which they anticipated him. Three of them, and also James Jurin (1684-1750), have been commented upon by Laplace in the second Supplement of the 10th book of his Mecanique celeste [4], but this discussion is very brief and its impartiality, naturally, may be suspected. Thus a new comparison appears to be in order.