Astronomical Instruments of the Imperial Observatory

A large woodcut illustration within a rectangular border depicts various geometric measurement techniques using calipers and compasses. In the upper section, a hand holds a pair of large calipers over a cylindrical object to measure its diameter. To the left, another pair of calipers stands upright. In the lower section, a hand holds a pair of curved calipers measuring a vertical cylindrical post attached to a rectangular base. To the right, another hand uses a pair of calipers to measure the diameter of a sphere, rendered with concentric circular lines. The background features stylized horizontal lines representing the ground and a small patch of vegetation on a slight incline to the right.

Figure Forty-Eight