Abstract

R. P. de Lamanon was trained in theology and philosophy, but he chose the career of a self-taught geologist/naturalist, later adding experimental physics to his skills. Recommended by Condorcet, Secretary to the Académie Royale des Sciences, for the post of ‘Naturaliste’ on La Pérouse's expedition, he carried out delicate measurements at sea requested by the Académie and made two important discoveries: the barometric tide at the equator, and the variation of magnetic intensity with latitude. Killed by natives of Samoa in 1787, his reports were long delayed in publication, inadequately presented, and some even lost. Except for brief recognition by von Humboldt many years later, Lamanon's pioneering measurements have been largely ignored or forgotten. This paper revives his memory