Scientific Instruments, King's Foot And Protractor, Butterfield Architect's Set, 18th Century

A set of two measuring tools, a protractor and a caliper (or half-compass), both signed by Butterfield for Michael Butterfield (1635-1724), a Parisian manufacturer of mathematical and astronomical instruments. The caliper is particularly interesting and bears the inscription "weight of cannonballs." These instruments may have been part of an architect's set. Half-compass: Length 11.5 cm, Width 2.5 cm. Protractor: Length 10 cm, Height 7 cm.