"By Jove, if the wind lulls we are done for!" thought Barcroft. "A fellow wouldn't stand a ghost of a chance after a sniff of that stuff. Wonder how long the gas lasts?"
A back eddy sent a faint tinge of chlorine over the prostrate trio. It was as much as Billy could do to restrain himself from tearing his handkerchief from his mouth and gasping for breath. Fuller coughed heavily, while the A.P. rose to a kneeling position. Had not Barcroft grasped him by the arm he would have toppled off the bough. Then came another rush of pure air and the danger was past.
It was nearly twenty minutes before the apparatus exhausted itself. For nearly half a mile the track of the gas could be followed. The rich dark earth was turned a sickly yellow. Trees on the edge of the adjoining field were literall
