There is another aspect of gas attacks which I have never seen mentioned, at what range from the initial impact points
of gas shells is the cloud of gas still lethal or effective ? Eventually it will disperse of course, but were attacks by gas
ever made against a prevailing wind by firing behind the lines behind the enemy and letting the gas blow back on them.
I am aware that this would involve the friendly side getting a dose, but if the lines were far enough apart would dispersal of
gas by the time the cloud has reached friendly lines be enough not to cause own casualties ?
David

It was not uncommon to bombard enemy lines with gas shells or Livens projectiles. Weather conditions were crucial, however, in determining if gas was used, and the effectiveness. Any significant breeze dissipated the effects, as did rain.

Robert