The Ritchie ledgers, now held by Ritchie Navigation, indicate that this
compass was manufactured on August 11, 1877, and sold to T.S. & J.D. Negus,
a New York firm that sold a variety of nautical and optical instruments. It
later belonged to the U.S. Coast & Geodetic Survey.
Ref: E. S. Ritchie & Sons, Ritchie’s Liquid Compasses and Nautical
Instruments (ca. 1905).