This is a stereoscopic viewer, a special device for looking at three-dimensional (3D) photographs. These were a popular form of home entertainment from Victorian times until after World War 1.
How does it work?
Using a stereoscopic camera, two photos were taken of the same scene from slightly different viewpoints (spaced apart like your eyes are). They were printed side by side and mounted on thick card, creating a stereoscopic photograph. This was slotted into a special holder in the stereoscopic viewer.
When you look through the viewer you see both images at the same. Your brain joins them together and it looks like you are seeing the scene in the real world. Stereo sound works in a similar kind of way.
This is one of a series of stereoscopic photos that shows the lives of Gurkha soldiers on the Western Front in France and Belgium in World War 1. In this image they are collecting rations (food) in the courtyard of a French farm.
Gurkha soldiers are from Nepal. They can be recognised by their distinctive slouch hats (wide brimmed felt hats).
Gurkhas were incredibly brave soldiers who fought in some of the major campaigns of World War 1 including Ypres, Gallipoli and at the Battle of Loos, where one battalion fought to the last man.
There were many nationalities fighting with Britain and her allies in World War 1: India, Africa, the West Indies, Australia, Canada and New Zealand.
Did you know?
Gurkha soldiers still serve in the British Army today and many soldiers and their families have made their home in Folkestone.