Apollonius of Perga

Apollonius of Perga was a Greek mathematician of the third and second centuries BC, known as the Great Geometer. Born in Perga in Pamphylia, in what is now Turkey, he studied in Alexandria under the followers of Euclid and later taught there, and he spent time at Pergamum, where he met Eudemus. His best known work, Conics, was written in eight books, of which the first four survive in Greek and the first seven in Arabic, and it introduced the terms parabola, ellipse and hyperbola. Pappus describes six other works, among them Tangencies, which shows how to construct the circle tangent to any three points, lines or circles. Apollonius also contributed to Greek mathematical astronomy and developed the hemicyclium, a sundial with its hour lines drawn on a conic section.