拍品专文
Francis Watkins is recorded as having worked between 1747 - 1784 and is located at Charing Cross between 1774 - 1782 when this instrument was made
细节
A rare mid-late 18th Century mahogany vernier octant
the ivory makers plaque engraved Made by Francis Watkins LONDON for Amos Sparkes 1779, the scale divided 5°- 0°- 95°, vernier divided 10 - 0 - 10 with fine screw adjustment, double pin hole sight, set of three shades, three mirrors and pencil in centre of 'T' frame, the reverse with brass pins for standing and inlaid ivory jotter, the arc -- 16½in. (42cm.); the index arm -- 19in. (48cm.)
See illustration
the ivory makers plaque engraved Made by Francis Watkins LONDON for Amos Sparkes 1779, the scale divided 5°- 0°- 95°, vernier divided 10 - 0 - 10 with fine screw adjustment, double pin hole sight, set of three shades, three mirrors and pencil in centre of 'T' frame, the reverse with brass pins for standing and inlaid ivory jotter, the arc -- 16½in. (42cm.); the index arm -- 19in. (48cm.)
See illustration
出版
Clifton, G Directory of Bristish Scientific Instrument Makers 1550 - 1851 Zwemmer 1996