5 in reversing plain theodolite reading to 1 minute of arc. 4-screw levelling head (c.1860).
Used for measuring horizontal and vertical angles in land surveying and for setting out works. A book of instructions for the use of theodolites is in the collection (see 1998/001).
This item was displayed prior to acquisition at the Institution of Municipal Engineers Centennial Exhibition, Brighton, June 1972.