N. Everitt afterwards received for his work that night, was thoroughly well earned. On December 12th Major R. E. Sugden was severely wounded in the arm by a bullet. The bridges over the Canal were always dangerous spots. Not only were they well marked by the enemy artillery, but machine guns, posted further to the north, could fire straight down the Canal in enfilade. It was while he was crossing one of these bridges that Major Sugden was hit. He had served continuously with the Battalion since it had been mobilised and his loss was greatly felt. (_d_) December 19th. The enemy first made use of poison gas in the spring of 1915, about the time the Battalion landed in France. On that occasion he employed pure chlorine, but in so weak a concentration that the results were not nearly so disastrous as they might have been. After this first trial--it was probably more an experiment than anything else--he made no use of gas on a large scale for several months. This was fortunate, for it gave allied scientists time to study the whole problem and to devise means of protection, not only against chlorine, but against other harmful gases also. It is true that anti-gas measures were far from perfect at the end of 1915. But the allied armies were better prepared for that form of attack than they would have been had they had no preliminary warning. In particular, the possibility of the enemy using phosgene had been guarded against by the introduction of the P.H. helmet. This was a considerable advance; its two stout glass eye-pieces were a great improvement on the single mica window of the P. helmet, and the outlet valve made it much less stuffy and more comfortable to wear. There is no doubt that, about the beginning of December, some rumour that the enemy was soon to try a second gas attack on the Ypres Salient had filtered through to the British. One of the reasons for the patrol of Sec.-Lieut. W. N. Everitt, already described, was to discover whether any gas cylinders were in position in the enemy lines. New P.H. helmets had been issued to all the men in the Battalion, but, as the available supply only admitted of one per man, a P. helmet was still carried as a reserve. Much gas helmet drill had been done, and all ranks were warned to be specially on the alert.