1013-1054

German scholar who wrote treatises on the astrolabe, the abacus, and the number game rithmomachia. Hermannus, son of Count Wolverad of Swabia, had from birth suffered from "contracted" or deformed limbs—hence his surname. He studied in the monastic school at Reichenau, where he later became abbot. As a teacher, Hermannus had a large student following.