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A fine and rare early 18th-Century French brass circumferentor,
Details
A fine and rare early 18th-Century French brass circumferentor,
signed Butterfied A Paris, the alidade with twin sights, one end with vernier, the other with single index line, the central glazed compass with engraved windrose, eight initialled compass points, circumference scale in four quadrants and blued-iron needle, the circle with circumference scales 1-360° and in four quadrants, and two pairs of slit sights, on a ball-and-socket joint with butterfly-handled screw clamp to a staff mounting
6in. (15.2cm.) diameter
signed Butterfied A Paris, the alidade with twin sights, one end with vernier, the other with single index line, the central glazed compass with engraved windrose, eight initialled compass points, circumference scale in four quadrants and blued-iron needle, the circle with circumference scales 1-360° and in four quadrants, and two pairs of slit sights, on a ball-and-socket joint with butterfly-handled screw clamp to a staff mounting
6in. (15.2cm.) diameter