4 0 c m
29cm
actual image size: 21cm x 32cm
Description
This instrument was designed primarily to ensure that a cannon or mortar was elevated to the required angle. Quadrants were also used for navigational purposes to determine the altitude between some heavenly body and the horizon. George Adams (1750-1795) was instrument maker to George III, as his father was before him.
Image Details
Image Ref.
10302750
© Science Museum / Science & Society Picture Library