On the left hand side an iron handle was situated: moving this handle up and down, an internal pump (in the copper fluid container) rushed the fluid under pressure through the hose an enabled the sprinklerhead to atomize the fluid.
In 1915 these sprinklers were used on the Western Front as a counter measure to the chlorine gas. The sprinklers were used to atomize a chemical solution, which dissolved the thick chlorine fog that floated close to the ground. The use of these devices is clearly documented by different photographs taken near the front, spring 1915. In October 1915, when a German reinforced sector (the so-called “Hohenzollern Redoubt”) was conquered during the Battle of Loos, every company of the 46th Division was equipped with one “Vermorel” sprinkler and 4 gallons (15 litres) of that particular chemical solution.
The sprinkler found in a trench dug in April-May 1915 can be related to the chlorine gas the Germans used in the Second Battle of Ypres (April-May 1915). Note that this was the first application of chemical warfare ever. Chlorine gas is a suffocation gas with a higher density than common air; it appears as a green- to yellowish cloud that floats close to the ground surface. When the gas makes contact with moisture (for example in lungs, eyes and skin) it triggers a chemical reaction that leads to severe burning wounds.
The initial symptoms of a chlorine gas intoxication are vomiting, difficulties with breathing and a burning sense in the lungs, eyes, throat and mouth. In case of a serious intoxication there occurs cellular damage to the lungs, which induces the level of fluids in the lungs, leading to the loss of consciousness an ultimately death. The victim basically drowns in the fluid gathered in his lungs.