Ampere, Andre Marie, born in 1775. A distinguished electrician who may be considered the father of electro-magnetics. He first attracted attention by a treatise on the "Theory of Probability," published in 1802, and obtained a post as teacher and ultimately as professor, at the polytechnic school in Paris. In 1820, Oersted's discovery of the effect of voltaic currents upon magnetic needles was brought to his notice, and Ampere verified and completed this, and showed also the mutual effect of currents upon each other, from which he deduced a new theory of magnetism. The Royal Academy of Sciences recognized his services, and gave his name to one of the electro-magnetic units. Ampere's last great work was the classification of the sciences, but this he did not live to finish. Died, 1836.