Optical Square Rangefinder c.1905 R. H. Stocken aluminium dial with black painted

aluminium dial with black painted centre and luminous paper markers

featuring his favourite Sopwith Camel and a deadly duel with a German ace

almost two miles from where the mine exploded

as they are simple and accurate'

The Barker M-72 compass was a direct descendant of the legendary MK III that was in use with the British armed forces throughout the second world war

Optical Square Rangefinder c.1905 R. H. Stocken aluminium dial with black paintedAn Optical Square rangefinder, dating from c. 1905, complete with its original fitted leather case. Reputed to have been invented by George Adams Senior in the middle of the 18th century, the optical square appeared in the 1795 catalogue of George Adams Junior as 'A small instrument for surveying by right angles'. In the 1907 Negretti & Zambra catalogue it was described as being used 'for fixing a right angle, and in the laying off of offsets'. A