Like Dennis himself, he was not one of those pert modern boys who think they know everything.
"What has the wind got to do with it?" said young Wetherby.
"Gas, old chap, gas!" replied the two brothers. "The moment you hear the alarm, ram on your gas helmet and see the tube is working."
"And by the living Jingo!" cried the major, "there it goes!" And he shot out of the dug-out into the trench as a man on the look out beat furiously upon an empty shell-case dangling there for the purpose.
"Pull it right down!" shouted Dennis, giving young Wetherby a helping hand with his helmet. "Now you're fixed. Wish there was a mirror handy; you've no idea how well you look in it, old man."
Despite the seriousness of the moment Wetherby roared with laughter inside the stifling, smelly cowl that made them both seem like familiars of the Spanish Inquisition.
And then, revolvers in hand, they took their places in the trench and waited.
"Are you certain it's gas?" said Dennis to Tiddler, who had sounded the alarm in their front, for beyond the parapet there was a strange stillness, and the night was as black as your hat.
"Yes, sir; I see it right enough, just as their last flare died down. I saw it at Hill 60, and I've 'ad some. It'll be 'ere in a tick."
But the enemy was impatient that night, and on a sudden a group of star-shells burst overhead, lighting everything up brilliantly, and revealing a long line of grey figures advancing stealthily.