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
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