In de schaduw van ’s Gravesande. Het Leids Physisch Kabinet in de tweede helft van de 18e eeuw

Under's Gravesande's shadow. The Leiden Physical Cabinet in the second half of the 18th century. During the later 17th and the first half of the 18th century, the university of Leiden became an important center for the propagation of the experimental method in natural philosophy, especially through the Newtonian professor of physics W.J. 's Gravesande. Through the acquisition, after his death in 1742, of his private collection of instruments, Leiden became arguably the best equipped university on the continent for the teaching of experimental physics. Drawing mainly on unexplored financial documents in the university archives, this paper traces the rather less heroic era, which followed that highlight period in the history of the Leiden Physical Cabinet. Concentrating on the years 1742 to 1811, it demonstrates that the cabinet by no means fossilized, but doubled in size through the acquisition both of new (table 1) and 'second-hand' (table 2) instruments by's Gravesande's successors. These were, respectively, P. van Musschenbroek, J.N.S. Allamand, C.H. Damen and S. Speyert van der Eyk, each of whom tried to keep the cabinet in step with new developments in the field. Many of the 18th-century instruments from the Leiden Physical Cabinet are on permanent loan in the National Museum for the History of Science and Medicine, Museum Boerhaave, in Leiden, and this provides an extra stimulus to explore its growth and vicissitudes during the post-'s Gravesande period. A catalogue of this collection was published by C.A. Crommelin in 1926; a revised English edition followed in 1951. As argued in this paper, there are reasons for compiling a new catalogue, but there are problems of identification, and these are also discussed.