5921667 Female munition worker preparing shells in a factory, 1916 circa (b/w photo) by Unknown photographer, (20th century); National Army Museum, London; (add.info.: Female munition worker preparing shells in a factory, 1916 circa. Photograph, World War One, 1916 circa. During World War One women volunteered for essential work in order to release men for service in the armed forces. Between 1914-1918, around two million women volunteers replaced men in employment. Many female munition workers suffered from the chemicals they worked with, which turned their skin yellow, prompting the nickname ?canaries?. Photograph from an album of 76 official photographs, 1916-1917.); by National Army Museum ; out of copyright.