Benjamin Rittenhouse (1740–1825) was born in Norriton, Pennsylvania, and probably learned to make clocks and compasses from his older brother, David Rittenhouse. He served as Superintendent of the American gunlock factory in Philadelphia during the Revolution, and returned to his house in Worcester Township after the war. The Pennsylvania Packet for May 14, 1785, published the following notice:
WANTED, An ingenious Lad not exceeding 14 years of age, of a reputable
family, as an Apprentice to learn the Art and Mistery of making Clocks and
Surveying Instruments. Any lad inclining to go an apprentice to the above
Trade, the terms on which he will be taken may [be] known by enquiring of Mr.
David Rittenhouse, in Philadelphia, or at the subscriber’s house in
Worcester township, Montgomery county. Benjamin Rittenhouse.
Benjamin Rittenhouse was the most prolific compass maker working in America in the late 18th century, and some three dozen of his instruments are now known. Those with only his signature date from the period 1785–1796. Those signed "Rittenhouse & Potts" were made in partnership with William Lukens Potts, and date from around 1796–1798. Those signed "Rittenhouse and Evans" were made in partnership with Benjamin Evans, and date from around 1798–1801. Rittenhouse went bankrupt in 1801, and spent his latter years in Philadelphia.
Ref:
Silvio A. Bedini, Early American Scientific Instruments and Their Makers (Washington, D.C., 1964).
Bruce R. Forman, "The Worcester Workshop of Benjamin Rittenhouse," Rittenhouse 2 (1988): 82–83.
Jeffrey D. Lock, "Construction Details of Rittenhouse Compasses," Professional Surveyor (December 2001): 28-34.