Circumferentor by G. Adams of London, used in 1763 on the survey of the Mason-Dixon line, 1725-1763
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.
- Object Number:
- furnishing and equipment
- measuring device - instrument
- magnetic compass
- Royal Geographical Society
- Unlinked Name
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