HIRN, ḗrn, (1815-90). A
French physicist, born at Logelbach, near
Colmar. When he was nineteen he entered his
grandfather's cotton factory as chemist; afterwards
he acted as engineer, and began his valuable
researches on mechanics, and especially on
calorics. He was made a member of the French
Academy of Science in 1867; in 1880 founded a
meteorological observatory near Colmar; and
later devoted himself to astronomy. Hirn was
educated in the shop, and his works are marked
by much practical criticism of mere academic
theory. They include: Theorie mecanique de la
chaleur (3d ed. 1875-76); Analyse de l'univers
(1869); Mémoire sur les anneaux de Saturne
(1872); Les paradynamometres (1870); Étude
sur une classe particuliere de tourbillons (1878); Recherches experimentales sur les relations entre la resistance de l'air et sa temperature (1882); La vie future et la science moderne (1882); and Constitution de l'espace celeste (1889).