Extremely rare mahogany Hadley quadrant, signed on the boxwood scale: 'Goater No.141 Wapping, LONDON', dated on the ivory: '1774'. The large quadrant has a mahogany frame with a hand engraved mahogany scale. The instrument retains its original, ivory, owner's plaque which is indistinctly engraved. The instrument retains its original brass peep sights, index mirrors and color filters. The radius arm has a standard lobster claw end, typical of the instruments of this period and retains the original ivory index. (I-482)
Condition: The instrument has wonderful age patina and has replaced feet.
Reference I: Clifton, Gloria, 'Directory of British Scientific Instrument Makers 1550-1851', National Maritime Museum, 1995, p. 114. John Goater worked between 1754 and 1786. In 1758, he moved opposite Execution Dock, Wapping, London. Reference II: A very similar instrument is illustrated on page 76 in: Wynter, Harriet and Anthony Turner, 'Scientific Instruments', New York: Charles Scribner's Sons, 1975.
Dimension: Height 20 inches.