Glenbrook Tunnel War One. The first was Chlorine gas which was introduced by the Germans at the Second battle of Ypres in April 1915. This was followed by the use of Phosphene Gas, also introduced by the Germans. These attacked victims' respiratory organs causing coughing and choking. The Germans used Mustard Gas, a more advanced gas, for the first time at Riga (or Yperite) in September 1917. It caused both internal and external blistering in its victims. The blistering was often delayed and remained in the ground for weeks afterwards making capture of infected trenches dangerous. Protection against mustard gas was far
Mines in the Battle of Messines (1917) Second Army (General Sir Herbert Plumer), remarked to the press, "Gentlemen, I don’t know whether we are going to make history tomorrow, but at any rate we shall change geography". The Battle of Messines marked the zenith of mine warfare. On 10 August 1917, the Royal Engineers fired the last British deep mine of the war, at Givenchy-en-Gohelle near Arras. As part of allied operations in the Ypres Salient, British mining against the German-held salient at Wijtschate near Messines had begun in spring 1915, with diggings below the surface. The concept of a deep mining offensive was devised in September