“ Soon, however, he turned his attention to the study of geography. In 1858 he obtained an appointment as teacher of geography at the Sorbonne, and henceforth devoted himself to that subject. It was not till 1876 that he published, in two volumes, his remarkable Histoire de la formation territoriale des états de l’Europe centrale, in which he showed with a firm, but sometimes slightly heavy touch, the reciprocal influence exerted by geography and history. While the work gives evidence throughout of wide and well-directed research, he preferred to write it in the form of a student’s manual ”