
When the United States entered WWI, it was decided to adopt types of artillery in use by the Allies to facilitate early quantity production and to secure as much uniformity in artillery materiel as possible. Accordingly, the United States was equipped with the 240-mm heavy Howitzer. Chemical shells were approved for this caliber; however, no available information suggests that chemical fills were implemented.
No information about functioning.
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Old Chemical Weapons and Related Materiel Reference Guide (2018)