Soldiers recount their experiences of poison gas attacks on the Western Front during World War One in BBC archive recodings. Poison gas was first used as a weapon in 1915 and by the end of the war, gas had killed 90,000 soldiers and affected one million.
(Photo: Gas casualties of the British Army 55th Division on the Western Front, dated 10 April 1918. Credit: Lightroom Photos/TopFoto)