Circumferentor, 1750-1763.

Image number: 10280187

Circumferentor, 1750-1763.

This circumferentor was made by George Adams of London, one of the top instrument makers of the day. It was used between 1750-1763 on the survey of the Mason-Dixon line, in America. The instrument is inscribed in an engraved circle; 'Geo: Adams LONDON'. Circumferentors (with a full circle scale) and graphometers (with a half circle scale) were widely used for angle measurement in the 17th and 18th centuries. A joint on the support allowed for both vertical and horizontal use.

Image number:
10280187
Credit:
Science Museum/Science & Society Picture Library
Date taken:
29 October 2003 13:13
Image rights:
Science Museum