Ancestor of the mechanical clock has been thought by some to be the sundial. Actually these devices represent two different approaches to the problem of time-keeping. True ancestor of the clock is to be found among the highly complex astronomical machines which man has been building since Hellenic times to illustrate the relative motions of the heavenly bodies.

            This study—its findings will be used in preparing the Museum's new hall on the history of time-keeping—traces this ancestry back through 2,000 years of history on three continents.

            The Author: Derek J. de Solla Price wrote this paper while serving as consultant to the Museum of History and Technology of the Smithsonian Institution's United States National Museum.