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A large 18th-Century French lacquered-brass graphometer,
细节
A large 18th-Century French lacquered-brass graphometer,
unsigned, with 20-0-90-0-20° scale, central glazed compass with engraved and shaped supports in the form of dragons, engraved windrose, cardinal points initialled in French, double circumference scale and edgebar needle, the alidade with twin sights and one vernier, four curved supports to a compass joint and the 11½-inch long telescope with objective dust-cap and sliding eyepiece tube adjustment, the reverse with bubble level and staff mounting incorporating a ball-and-socket joint with screw clamp
13½in. (34.3cm.) wide
unsigned, with 20-0-90-0-20° scale, central glazed compass with engraved and shaped supports in the form of dragons, engraved windrose, cardinal points initialled in French, double circumference scale and edgebar needle, the alidade with twin sights and one vernier, four curved supports to a compass joint and the 11½-inch long telescope with objective dust-cap and sliding eyepiece tube adjustment, the reverse with bubble level and staff mounting incorporating a ball-and-socket joint with screw clamp
13½in. (34.3cm.) wide