Scientific Instrument Society 25th Anniversary Exhibition
44 'Gun-Barrel' Theodolite
An early theodolite for use in surveying, with the telescope tube shaped like the barrel of a gun. This was a fundamentally new design in 1737, and marked the origin of the modern, stable and accurate theodolite.
The instrument is signed ‘J Sisson London’; Jonathan Sisson flourished c. 1690-1747. As well as making surveying instruments, Sisson produced large astronomical instruments for observatories across Europe.
Private Collection, U.K.
See: W. Gardiner, Practical Surveying Improved, London 1737.
Objects lent by Anonymous Lender IV, UK: