White Cross (Weisskreuz) is a World War I chemical warfare agent consisting of one or more lachrymatory agents: bromoacetone (BA), bromobenzyl cyanide (Camite), bromomethyl ethyl ketone (homomartonite, Bn-stoff), chloroacetone (Tonite, A-stoff), ethyl bromoacetate, and/or xylyl bromide.
During World war I, White Cross was also a generic code name used by the German Army for artillery shells with an irritant chemical payload affecting the eyes and mucous membranes.
References
White Cross (chemical warfare) Wikipedia(Text) CC BY-SA