Benjamin Rittenhouse, brother of clock maker and astronomer David Rittenhouse, was born in 1740 in Norriton, Pennsylvania. An ardent patriot, he joined the army during the Revolution and was wounded at Brandywine. While Rittenhouse worked as a clock and mathematical instrument maker throughout his lifetime in Philadelphia, he also held several influential posts in the community as the superintendent at the Philadelphia Gun Lock Factory in 1778, and in 1791 becoming judge of the Court of Common Pleas in Montgomery County. Rittenhouse died in 1825 at the age of 84. For more biographical information on the Rittenhouse family, see Daniel Colb Kassel's A Genea-biographical History of the Rittenhouse Family: and all its Branches in America, (Philadelphia, 1893). More examples of similar suveyor's compasses are illustrated in James Biser Whisker, Pennsylvania Clockmakers, Watchmakers, and Allied Crafts, (Cranbury, 1990), pp. 235-239.