‘Through gas and smoke, our troops advance to the final assault of Passchendaele Ridge’, 1917...

‘Through gas and smoke, our troops advance to the final assault of Passchendaele Ridge’, 1917. Photograph, World War One, Western Front (1914-1918), 1917. The Germans first used gas against the French during the capture of Neuve Chapelle in October 1914 when they fired shells containing a chemical irritant that caused violent fits of sneezing. In March 1915 they used a form of tear gas against the French at Nieuport, and the following month chlorine gas against the Canadians at Ypres. These early experiments were but a small taste of things to come and as the war progressed all sides developed ever more lethal gases including phosgene and mustard gas. From a collection of 101 stereoscopic photographs entitled ‘The Great War’.