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
Gas mask wearer to breathe the safer air found there. In addition, moist sponges were inserted at the end of the hoses in order to better filter the air. This was later modified to include its own air supply, leading to World War I era gas masks.<ref name="pbs.org/wgbh/theymadeamerica2"></ref><ref name="encyclopedia.com/topic/Garrett_Morgan2"></ref><ref name="biography.com/people/garrett-morgan2"></ref> The German army used poison gas for the first time against Allied troops at the Second Battle of Ypres, Belgium on 22 April 1915. As an immediate response was cotton wool wrapped in muslin issued to the troops by 1 May. This was followed by the Black Veil Respirator, invented by John