American Ebony Back-Staff
- Sold for:
- Clocks, Watches & Scientific Instruments - 2345
- Date / Time :
- July 29, 2006 10:00AM
American Ebony Back-Staff, with bone plaque marked Made by J. Halsy, Boston, for Thomas Setts, 1706, inscribed lines, boxwood sight and arcs, the great arc with scroll terminal and punchwork star decoration, divided with transversal scale 0-25°, the lesser arc 0-60° in both directions, lg. 22 1/2 in.
Literature: Note: Silvio Bedini, (1975), Thinkers and Tinkers, fig. 15, for a late 17th century pearwood backstaff similarly marked. Joseph Halsy is known to have made surveying compasses and instruments in Boston in the 18th century (he was married in Boston in 1731). It is unlikely that the plaque is original to this instrument, however it may be an early home-made replacement.