Description

5 in reversing plain theodolite reading to 1 minute of arc. 4-screw levelling head. The instrument was used by City Road Surveyor’s staff. Used for measuring horizontal and vertical angles in land surveying and for setting out works.

Box with trade card for “Thomas Dunn, Optician, Mathematical and Instrument Maker, 50 North Hanover Street, Edinburgh”; stamped on lid is “T[heodolite] 6” and a brass plate is engraved “CITY OF EDINBURGH ROADS DEPARTMENT 1883”

Single azimuth reading microscope; crossed levels and compass on vernier plate. Objective cap for telescope and blank in eyepiece sleeve; cross-wire intact. Lacks erecting eye piece, plumb bob and small accessories. Case lacks leather bands and one telescope support block. Case woodwork repaired and metal parts cleaned at the Royal Scottish Museum, 1972. Replacement screws and hinges. Catches are earlier replacements.

A book of instructions for the use of theodolites is in the collection (see 1998/001)

This item was exhibited at the “Institution of Municipal Engineers Exhibition” Brighton, 19-23 June 1972, stand 20; the “Exhibition of Municipal Engineering in Edinburgh, Past and Present” Edinburgh, 12-14 June 1973 (item 63) and the “Exhibition of Civil Engineering Works”, Glasgow, 21 September – 23 October 1977.