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
Tanks in the German Army at front and rear as well as several machine-guns, and reach a top speed of at least 12 km/h. The running gear was based on the Holt tractor, parts for which were copied from examples borrowed from the Austrian army. After initial plans were shared with the Army in December 1917, the design was extended to be a universal chassis which could be used as a base for both a tank and unarmoured "Überlandwagen" ("Over-land vehicle") cargo carriers. Powered by two Daimler engines, the tank was first demonstrated in the Spring Offensive of 1918. Internally, the Sturmpanzerwagen was cramped, smelly