Sulfur mustard later also against the French Second Army. The name Yperite comes from its usage by the German army near the town of Ypres. The Allies did not use mustard agent until November 1917 at Cambrai, France, after the armies had captured a stockpile of German mustard shells. It took the British more than a year to develop their own mustard agent weapon, with production of the chemicals centred on Avonmouth Docks. (The only option available to the British was the Despretz–Niemann–Guthrie process). This was used first in September 1918 during the breaking of the Hindenburg Line. Mustard agent was dispersed
Actions of 30 September – 4 October 1917 Actions of 30 September – 4 October 1917 The Actions of 30 September – 4 October 1917 were German methodical counter-attacks ("Gegenangriffe") during the Third Battle of Ypres in Flanders, during the First World War. Hasty counter-attacks () by the German 4th Army during the Battle of the Menin Road Ridge on 20 September and the Battle of Polygon Wood on 26 September, had been costly failures. On 29 September, a review was held at Roulers by Erich Ludendorff the (Quartermaster-General of the German Army, equivalent to the British Chief of the General Staff) with the commanders of "Heeresgruppe Kronprinz