BECQUEREL, ANTOINE CESAR (1788-1878). The first of several generations of distinguished French physicists. He was born at Chfitillon snr-Loing, in the Department of Loirct. 180S he entered the French Army as an officer of engineers, and served with distinction in Spain under Marshal Suchet. On his return to France he was appointed inspector of the Ecole Poly technique, and after serving in that capacity and with the general staff of the army, at the Peace of 1815 retired from active service to pursue scientific studies. Ile became professor of physics at the Museum of Natural History in Paris in 1837. His attention was principally devoted to electricity and magnetism, and among his researches are many important discoveries. While studying the physical properties of yel low amber Becquerel had occasion to make ex periments on the liberation of electricity by pres sure. This led him to investigate the laws governing the production of electricity by chem ical action. The result of his study was the overthrow of Volta's theory of contact, and the construction by him of a constant cell. The pro duction of a current by contact between differ ent pieces of the same metal and tbe determina tion of the resistance of various liquids and atmospheric electricity were also investigated, and he was greatly interested in meteorology and thermo-eleetric apparatus. He also dis
covered a method of determining the internal temperature of human and animal bodies, and in physiological investigations demonstrated that when a muscle contracts there is a development of beat. Becquerel may he considered one of the creators of ele•tro-chemistry. His labors in this branch of science secured for him election to the Paris Academy of Sciences. After 1828 he applied electro-chemistry in the reproduc tion of mineral substances mid in various electro lytic processes. In 1837 he was elected a mem ber of the Royal Society of London, and received the Copley Medal. Among his works, in several of which he had the cooperation of his son, Alex andre Edmond, were the Traite de l'eleetricite et du magneti8me ( 1855 ) ; Element d'eleetro chimic (1843) ; Traite de physique (1842) ; Ele ments de physique terrestre et de meteorologic (1847) ; Resume de l'hi-stoire de l'eleetricite et du magnetisme (1858).