AMPERE, ANDRE MARIE French physi cist, was born at Polemieux, near Lyons, Jan. 22, When Lyons was taken by the army of the Convention in 1793, the father of Ampere, holding the office of juge de paix, was thrown into prison, and soon after perished on the scaffold. This event produced a profound impression on the susceptible mind of Andre Marie, and for more than a year he remained sunk in apathy. From about 1796 he gave private lessons at Lyons in mathematics, chemistry and languages; and in 180I he removed to Bourg, as professor of physics and chemistry, leaving his ailing wife and infant son at Lyons. His wife died in 1804 and he never recovered from the blow. In 1809 he became professor of mathe matics at the Ecole Polytechnique in Paris. Here he continued his scientific researches and multifarious studies with unabated diligence. He was admitted to the Institute in 1814.
It is on the service that he rendered to science in establishing the relation between electricity and magnetism and in developing the science of electromagnetism, or, as he called it, electro dynamics, that Ampere's fame mainly rests. On Sept. II, 182o, he heard of H. C. Oersted's discovery that a magnetic needle is acted on by a voltaic current. On the i8th of the same month he presented a paper to the Academy, containing a far more complete exposition of that and kindred phenomena (see ELEC TROKINETICS). The whole field thus opened up he explored with characteristic industry and care, and developed a mathematical theory which not only explained the electromagnetic phenomena already observed but also predicted many new ones. His original memoirs on this subject may be found in the Ann. Chim. Phys. (1820-1828). Late in life he prepared a remarkable Essai sur la philosophie des sciences, and wrote many scientific papers, includ ing two on the integration of partial differential equations (Jour. Ecole Polytec/in., x., xi.) . He died at Marseille on June I o, 1836. The great amiability and simplicity of Ampere's character are well brought out in his Journal et correspondance (1872).