
3 4 c m
40cm
actual image size: 32cm x 26cm
Description
These callipers can be used to measure the diameter of cannon balls or, with crosed arms, to measure the bore of a cannon. The arms are inscribed with tables containing information relating to artillery. The instrument was made by Thomas Wright (d 1767), who styled himself mathematical instrument maker to George, Prince of Wales, in 1718.
Image Details
Image Ref.
10328261
© Science Museum / Science & Society Picture Library