Simple gas mask

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World War One (WWI), known as the “chemists’ war,” was the first time that chemical weapons were used for killing thousands of people on the battlefield at a time. By the war’s end, world leaders mobilized to contain the horrific and deadly agents of mass destruction.

A very simple "gas mask used during WWI by the allies in the campaign in France, circa 1915.

Sound the alarm

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A German signal alarm warned when their gas was being released. This photo was taken circa 1916.

Gas warning

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A German soldier bangs on a suspended frying pan to warn of a gas attack.

American nurse

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An American nurse wears her gas mask while working in the trenches near the front.

American soldier

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An American soldier stands guard during a German gas attack in France, circa 1918

Postcard from 1917

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Jan. 1, 1917, Unbekannt, Germany. This historic drawing on a postcard from 1917 shows a propaganda portrayal of a ''Gas Alarm'' in the German bunker on a WWI battlefield.

Anti-aircraft gun

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German artillery soldiers wearing gas masks pose with a quick-firing anti-aircraft gun used mainly against low-flying airplanes.

Blowing in the wind

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German soldiers take advantage of a suitable wind to release poison gas from cylinders.

French soldiers

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August 1915: French soldiers load artillery shells while wearing masks to protect against gas attacks.

French troops

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Circa 1915: French troops wear an early form of gas mask in the trenches during the second Battle of Ypres.

Gas shell bursting

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Circa 1916: A gas shell bursts at a road block on the Italian front.