Denis Papev, a French physicist, born in Blois in 1647, died in Marburg, Germany, about 1712. He practised medicine in Paris for some time, but turned his attention to mechanics, and became the assistant of Huygens. He visited England in 1680, and while there prepared his Dissertation sur la maniere d'amollir les os, et de faire cuire toutes sortes de mandes en fort peu de temps et dpeu de frais, avec la description de la machine (Paris, 1682). In this work he explained his digesteur or mar-mite, a contrivance for softening bones, the principle of which is still in use under the name of " Papin's digester." Having removed to Germany on account of the persecution to which he was exposed in France as a Protestant, he was appointed in 1687 professor of mathematics in the university of Marburg, and devoted his leisure to researches upon the use of steam. As early as 1690 he published the results of his labors in the Acta Eruditorum of Leipsic, proposing steam as a universal motive power, and describing a steam engine and even a rude paddle steamer.

It appears from documents discovered by Prof. Kuhlmann in 1852 in the public library at Hanover, that in 1707 he had a vessel built in conformity with his invention, and tried it on the Fulda. His last published work was a Latin "Essay upon a new System for raising Water by the Action of Fire" (Frankfort, 1707).