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 the night. An intelligence summary of the Second Army assessed the German artillery in support of the of 25 September, to have been the greatest concentration of artillery on a German divisional sector ever known and was nearly four times the usual quantity for a division. The attacking battalions had assembled during the night of covered by parties of the line-holding battalions opposite the 33rd Division. The great mass of German artillery began a bombardment at but fell short and German infantry fired red flares to signal to the German artillery that they were falling short, especially on the III