The Great War - WW1
Chemical Warfare
At 5pm on the 22nd of April 1915 two sinister greenish-yellow clouds crept across 'no mans land' towards the Allied lines in Ypres. They were pressurised chlorine gas released from over 500 cylinders in the German trenches as the preliminary to a major offensive. German prisoners and a deserter had warned of this new tactic, but no countermeasures had been taken. The two French colonial divisions on the north flank of the Ypres salient were engulfed by the cloud and fled in panic, leaving a four-mile gap in the front peopled only by the dead and those who lay suffocating in agony from chlorine gas poisoning. Having achieved total surprise, the Germans failed to exploit the breakthrough. Nevertheless, the gas had caused at least 15'000 casualties, 5'000 of them fatal.
Chlorine gas poisoning led to a slow and agonising death by asphyxiation. On the 25th of September 1915 the British released chlorine gas on the German lines at Loos but little of it reached the enemy trenches. Thereafter increasing use was made of gas shells. Some 63 types of gas had been developed by 1918 but the most familiar was mustard gas, which literally rotted the body from inside-out.
The first countermeasures against the gas were primitive, among them pads of cotton waste soaked in urine. The chlorine gas was partially neutralised by the ammonia in the urine. The famous box respirator did not appear until the winter of 1917 and soon became standard issue for troops at the front. Gas caused nearly a million casualties during the war, although this is only a conservative estimate.