The engineer, mathematician, and inventor Heron of Alexandria (active ca. AD 60) ranks among the most important scientists of the ancient Roman world in the tradition of Aristotelian experimentation.

Heron, about whose personal life virtually nothing is known, resided in Alexandria, Egypt, among the scientists and men of letters of the late Ptolemaic and Roman eras who dwelled around the famed library and museum. A brilliant theoretical scientist and a prolific writer, Heron wrote with clarity and insight. The knowledge of his writings and scientific investigations was preserved in the writings of the late Roman, Byzantine, and Arabic scientists and encyclopedists.

One of Heron's outstanding treatises was the Metrica, a geometrical study, in three volumes, on the measurement of simple plane and solid figures from polygons to hendecagons. It approximates the areas of triangles, polygons, quadrilaterals, ellipses, spheres, circles, and cones, and the volumes of various solids, including the...