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
18th Army (German Empire) 18th Army (German Empire) <nowiki></nowiki> The 18th Army () was an army level command of the German Army in World War I. It was formed against France on 27 December 1917 from the former Heeresgruppe Woyrsch command. It served exclusively on the Western Front and was dissolved on 2 January 1919. 18th Army was one of three armies (along with 17th Army and 19th Army) formed in late 1917 / early 1918 with forces withdrawn from the Eastern Front. They were in place to take part in Ludendorff's Spring Offensive. The Germans had realised that their only remaining chance of