Philipp Matthäus Hahn

Philipp Matthäus Hahn (1739 to 1790) was a German pastor, astronomer and inventor, born in Scharnhausen in the Duchy of Württemberg and active until his death in Echterdingen. About 1763 he devised a precision sundial, a heliochronometer that incorporated the correction for the equation of time, and in 1774 he designed one of the earliest mechanical calculators, of which two are known to survive. A renowned clockmaker, he is represented in several horological museums, including the Deutsches Uhrenmuseum, which holds a mechanical orrery and a Weltmaschine by the Priestermechaniker, the priest mechanic. His calculators place him among the early builders of calculating machines.