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
German Type U 93 submarine German Type U 93 submarine Type 93 was a class of U-boats built during World War I by the Kaiserliche Marine. Type 93 U-boats carried 16 torpedoes and had various arrangements of deck guns. As with the type 81 and 87, some had only one SK L/30 deck gun while others had a single SK L/45 gun and some were initially equipped with both. In 1917 some of the boats were refitted with a single 10.5 cm gun and 220 rounds. These boats carried a crew of 39 and had excellent seagoing abilities with a cruising range of around .