Rangefinder

Archibald Barr and William Stroud, professors of engineering and physics respectively at the University of Leeds in the 1880s developed the prototype of this optical rangefinder in response to a competition from the War Office. The instrument was adopted, first by the Navy and then the Army, and was widely used during WW1. Meanwhile Barr and Stroud had resigned their posts at Leeds to set up the company, Barr and Stroud, optical instrument makers – a company that lasted for almost 100 years. The model shown here, the FT 27 with a 0.8m base, was used by the infantry in WW1, and presented to the University in 1923.