Matthew Berge (d. 1819) worked for Jesse Ramsden in London, succeeded to the business after Ramsden’s death in 1800, used the Ramsden dividing engine, and numbered his sextants in the sequence begun by Ramsden. This example was made in the early 1800s. It has a "double" brass frame and a silvered scale. The scale is graduated every 15 minutes from -2o to +136o and read by vernier with tangent screw and magnifier.
A label in the box relates the instrument’s history. "SEXTANT owned
and used by JOHN C. FREMONT on his trip across the continent to CALIFORNIA. Presented by his Daughter, ELIZABETH B. FREMONT, to HON. CHARLES SILENT and by him to FRANK J. THOMAS. Loaned to and used by WELLS MORRIS on U.S. Destroyer "MUGFORD" in GREAT WAR."
Ref: A. Stimson, "The Influence of the Royal Observatory at Greenwich upon the Design of 17th and 18th Century Angle-Measuring Instruments at Sea," Vistas in Astronomy 20 (1976): 123-130.