“Am enclosing herewith my picture taken after standing out a phosgene gas attack. ½ hour test in the gas chamber and a one hour hike with helmet. It was some ordeal the last stage of the hike but the respirator is a positive protection against anything the Germans can let loose.”

Letter of 1st Lt. Daniel Joseph Birmingham,
28th Inf., Co. M, March 11th, 1918.

Diary Courtesy of the
Col. Robert R. McCormick Research Center

Above: Soldiers on a march wearing their gas masks.  Signal Corps Photograph Courtesy of the Colonel Robert R. McCormick Research Center.