The Fourth Canadian Battalion at one moment came under a particularly withering fire. For a moment--not more--it wavered. Its most gallant commanding officer, Lieut. Col. Burchill, carrying, after an old fashion, a light cane, coolly and cheerfully rallied his men and, at the very moment when his example had infected them, fell dead at the head of his battalion. With a hoarse cry of anger they sprang forward, (for, indeed, they loved him,) as if to avenge his death. The astonishing attack which followed--pushed home in the face of direct frontal fire made in broad daylight by battalions whose names should live for ever in the memories of soldiers--was carried to the first line of German trenches. After a hand-to-hand struggle the last German who resisted was bayoneted, and the trench was won. The measure of this success may be taken when it is pointed out that this trench represented in the German advance the apex in the breach which the enemy had made in the original line of the Allies, and that it was two and a half miles south of that line. This charge, made by men who looked death indifferently in the face, (for no man who took part in it could think that he was likely to live,) saved, and that was much, the Canadian left. But it did more. Up to the point where the assailants conquered, or died, it secured and maintained during the most critical moment of all the integrity of the allied line. For the trench was not only taken, it was held thereafter against all comers, and in the teeth of every conceivable projectile, until the night of Sunday, the 25th, when all that remained of the war-broken but victorious battalions was relieved by fresh troops. It is necessary now to return to the fortunes of the Third Brigade, commanded by Brig. Gen. Turner, which, as we have seen, at 5 o'clock on Thursday was holding the Canadian left, and after the first attack assumed the defense of the new Canadian salient, at the same time sparing all the men it could to form an extemporized line between the wood and St. Julien. This brigade also was at the first moment of the German offensive, made the object of an attack by the discharge of poisonous gas. The discharge was followed by two enemy assaults. Although the fumes were extremely poisonous, they were not, perhaps having regard to the wind, so disabling as on the French lines, (which ran almost east to west,) and the brigade, though affected by the fumes, stoutly beat back the two German assaults.