Rare 20 inch Mahgany, brass and ivory quadrant unsigned English, circa 1790. The instrument has an all wood frame and sliding mahogany radius arm with a stepped brass fitting at the end with an ivory vernier scale.  The bottom arc of the instument has an inlaid ivory engraved scale with marking 0-90 degrees. Near the center of the instrument is a curved stretcher with a blank ivory maker's label below the turned bone pencil holder. The instrument is compleate with index mirrors, pair of color filters, 2 peep sights and three brass feet. The instrument retains the original pie shaped step up box with the owner's name 'B ARCHER' stenclied on the top of the raised section of the lid. The inside of the lid bears the orginal makers label which is engraved 'Thos. Swann Mathamatical Instument... Maker No. 3 Liverpool'. (I-898)
Condition: The instument and the box are in fine condition and have a mellow age patina.
Dimensions of Instrument: Height 20 inches. Width 16 3/4 inches, Depth 2 7/8 inches
Dimensions of Box: Height 21 inches, Width 18 1/2 inches Depth 4 inches.