Ypres east of the town. The first gas attack occurred against Canadian, British, and French soldiers, including both metropolitan French soldiers as well as Senegalese and Algerian tirailleurs (light infantry) from French Africa. The gas used was chlorine. Mustard gas, also called Yperite from the name of this town, was also used for the first time near Ypres, in the autumn of 1917. Of the battles, the largest, best-known, and most costly in human suffering was the Third Battle of Ypres (31 July to 6 November 1917, also known as the Battle of Passchendaele), in which the British, Canadian, ANZAC, and
Action of 25 September 1917 removing more guns from the Third Army and Fourth Army, which were further south in Artois and Picardy. The increased amount of heavy artillery was to be used to destroy German concrete shelters and machine-gun nests, which were more numerous in the German battle zones, than the outpost zones which had been captured in July and August and to engage in more counter-battery fire. Few German concrete pill-boxes and machine gun nests had been destroyed during earlier preparatory bombardments and attempts at precision bombardment before attacks had also failed. The and guns and howitzers in the Second Army on 31