Last year Falkenhayn threw German forces at the Belgian town of Ypres, trying to overwhelm the British and French defenders before pushing on to the Channel ports. The Germans were unable to break through and after a month of fighting Falkenhayn called a halt to the assault. Since then the Germans at Ypres have largely sat on the defensive.
That changes today. In the early evening, Falkenhayn launches another massed assault on the Allied line, this time targeting French troops in the vicinity of Langemark. The German attack is preceded by an intense artillery bombardment, which must have warned the defenders of what was coming their way. But the full horror is unexpected. At about 5.00 pm a strange yellow-green cloud starts to waft from the German positions, before being blown on the wind towards the French lines.
When the cloud reaches the French trenches its foul nature becomes apparent. The French and North African troops find themselves choking and gasping for breath, their eyes stinging and burning. The Germans are attacking them with chlorine, a poison gas. Chlorine is heavier than air, so it sinks into the French trenches. The defenders climb out of their positions to try and find clean air, but then they are cut down by German gunfire.
Some of the defenders flee for their lives, managing to get away before the gas kills them. Officers to the rear are shocked to see these men running as fast as they can, equipment and weapons abandoned in their desperate flight, but the faint pungent smell on the wind and the sight of the men coughing and spluttering with foamy mouths and starting eyes makes clear that something terrible has happened.
The architect of Germany’s chemical warfare programme is the chemist Fritz Haber. He sees gas as a weapon that can end the war and bring victory to Germany. Germany has signed international agreements repudiating the use of poison gas in war, but this is dismissed as no longer relevant; in any case, Germany had also signed treaties guaranteeing Belgium’s neutrality.
Gas has already been used experimentally in the East, at Bolimów, but the cold weather limited its effect. In the Belgian spring it proves much more effective. On this day alone the chlorine cloud inflicts some 6,000 casualties on the French, many of whom are killed or blinded.
A hole has been cut in the Allied line, yet the Germans do not exploit this success by sweeping down to Ypres itself. Although they are equipped with gas masks, the Germans are wary of marching into the gas cloud (and with good reason, as they suffer many casualties from their own poisonous weapon). When they do push forward, they do so tentatively, not realising the weakness of the enemy in front of them.
Nearby Canadian troops attempt to plug the gap in the Allied line. They improvise gas masks by urinating on cloth rags and holding them to their faces. In confused fighting before and after the fall of night the Canadians are able to halt the German advance.
Poison gas being released (Wikipedia; the picture is not necessarily of gas being released at Ypres)
Fritz Haber (Wikipedia)
The Gas Attack: 22nd April 1915 (Webmatters: First World War, Carte de Route)