German Army chemical mortars

With the Rhine behind them the Allies pushed deeper into German territory, and although there was some bitter resistance left in the enemy, it was to be only sporadic. Chemical mortar battalions accompanied the armies in their advance but much of the time, as in northern France, the rapid movement eliminated the need for their employment. And so, as the European war came to an end, some of these battalions were already serving in nonoperational and occupational capacities. This was as it should have been they had done their measure of fighting and had acquitted themselves well. 

The German Army came close to the American Army in its stockpile of mustard filled shells, some 400,000 10-cm. mustard-arsenol shells coming to light after the war. No other chemical mortar shells were found. They either may have decided that other fillings were not satisfactory or else they were not able to put other shells into production. ... 

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