Theodolite, cased, No.117682, by Hilger and Watts, London, 1959.
Theodolites are used in land surveying to measure angles between points on the vertical and horizontal axes. A telescope is mounted so that it can rotate around the axes and give accurate readings, down to the milliradian.
Hilger and Watts were a British manufacturing company which made scientific instruments. At its peak the company employed around 1300 people in six factories in the South East of England.