Details
An early mining theodolite,
signed on the silvered compass dial Troughton and Simms, London, the instrument arranged for use as either a theodolite or mining dial, with vertical half-circle, telescope and bubble-level, raised on twin supports from the compass limb with level and cross-bubble, fitted for use with two folding sights, the compass with twin verniers, the balanced edge-bar needle on jewelled pivot and arranged for rotation for fine adjustment by internal rack and pinion gear, the needle with clamp lever and compass locking pin, the staff or tripod attachment stamped 197, with accessories including three tripod feet, in fitted mahogany case -- 10¼in. (26cm.) wide
See Illustration
signed on the silvered compass dial Troughton and Simms, London, the instrument arranged for use as either a theodolite or mining dial, with vertical half-circle, telescope and bubble-level, raised on twin supports from the compass limb with level and cross-bubble, fitted for use with two folding sights, the compass with twin verniers, the balanced edge-bar needle on jewelled pivot and arranged for rotation for fine adjustment by internal rack and pinion gear, the needle with clamp lever and compass locking pin, the staff or tripod attachment stamped 197, with accessories including three tripod feet, in fitted mahogany case -- 10¼in. (26cm.) wide
See Illustration