Blue Cross (chemical warfare)

Blue Cross gas (Blaukreuz): A "Sneezing" gas and chemical warfare agent so called from the standard Blue Cross marking for German artillery shells with a chemical payload. It was introduced by the Germans in 1917. It consisted of (DA, Clark I),  (CDA, Clark II),  (Dick), and/or  (Methyldick). Clark I and Clark II were the main agents used and affects the upper respiratory tract.

Clark I was used with Green Cross munition earlier; however for the first time it was used as a standalone agent in the night from 10 July to 11 July 1917 at Nieuport, Belgium, during "". The artillery munition used as a delivery vehicle contained a large amount of glass spheres closed with a cork and sealed with. Later N-ethylcarbazole was added. Depending on the caliber, the munition contained between 7 and 120 kilograms of the agent.