Xylyl Bromide, T-stoff, white cross (German), or methylbenzyl bromide, was used as a tear gas in World War I under the name Weisskreuz. It was a popular agent due to its easy manufacture. Its first use is dated to August 1914, when the French used tear gas grenades with xylyl bromide on Germans.
Xylyl bromide was the active ingredient in the T-shell, an artillery shell with explosive in its front part, filled with the liquid agent and named after Hans von Tappen, its inventor. On January 30, 1915, it was used against Russians.
Gas masks offered good protection against xylyl bromide.
The CAS number is for o-xylyl bromide (2-methylbenzyl bromide), for p-xylyl bromide (4-methylbenzyl bromide), and for m-xylyl bromide (3-methylbenzyl bromide). Number is reported as well.