Keuffel & Esser termed this a "high grade" sextant as made for the U.S. Navy. The frame is gun metal. The scale is silvered, graduated every 10 minutes from -5o to 155o and read by vernier with tangent screw and magnifier to 10 seconds of arc. The serial number indicates that it was made in 1900. New it cost $120. Ref: Keuffel & Esser, Catalogue (New York, 1906), p. 414.