The trench periscope is an optical device that soldiers used during the First World War to observe the ground in front of their trenches and fortifications, without taking the risk of raising their head above the parapet and becoming a target for enemy snipers.
Such challenges had to be overcome since sentries needed to be able to watch over no-man’s-land to warn of enemy attack and the artillery observers needed to be able to scrutinize enemy positions to identify targets and to gauge the accuracy of gunfire.
This particular periscope was one with an uncommon design. It was made by James W Lees Company of Manchester, England. The device was simple; a mirror is located at each end of the leather-bound tube.