Simple theodolite and case, 1771-1781

Simple theodolite, with box, trade card and brass parts, by James Search of London, 1771-1781

Simple theodolites such as the circumferentor (with a full circle scale) and graphometer (with a half-circle scale) were widely used throughout the 17th and 18th centuries for angle measurement. A joint on the support allowed for both vertical and horizontal use. The tradecard on the box lid indicates that this circumferentor was made by James Search (active 1771-1781), a Mathematical, Philosophical and Optical Instrument maker who made and repaired instruments 'At the Globe in Crown Court, St Ann's Soho, London'.

Details

Category:
Surveying
Object Number:
1944-11
Materials:
oak (wood), brass (copper, zinc alloy), iron, glass and complete
Measurements:
box: 114 mm x 383 mm x 383 mm,
socket: 145 mm,
type:
simple theodolite
credit:
Winn, G.W.

Parts

Simple theodolite, English, 1771-1781

Simple theodolite, English, 1771-1781

Simple theodolite, by James Search of London, 1771-1781

More

Circumferentors (with a full circle scale) and graphometers (with a half-circle scale) were widely used throughout the 17th and 18th centuries for angle measurement. A joint on the support allowed for both vertical and horizontal use. The tradecard on the box lid reads: 'Mathematical/ Philosophical and Optical/ INSTRUMENTS/ Made and Repaird in the best Manner/ At the Globe in Crown Court, St Ann's Soho,/ London/ BY/ James Search, Instrument Maker'.

Materials:
complete , brass , iron and glass
Object Number:
1944-11 Pt2
type:
instrument component and simple theodolite
Image ©
The Board of Trustees of the Science Museum