Up to now the battalion, singularly enough considering the amount of shelling that was going on, had escaped with comparatively few casualties, but they were not to escape much longer. As their line trickled slowly down the communication trench, Pug had no more than remarked on how cheaply they had got off so far, when a six-or eight-inch high-explosive shell dropped with a rolling _crump_, that set the ground quivering, close to the communication trench. The men began to mend their pace, and to hurry past the danger zone, for they knew well that where one shell fell there was almost a certainty of others falling. A second and a third shell pitched close to the other side of the trench, but the fourth crashed fairly and squarely into the trench itself, blowing out a portion of the walls, killing and wounding a number of men, and shaking down a torrent of loose earth which half choked and filled that portion of the trench. The communication ways, and, indeed, all trenches, are constructed on a principle of curves and zig-zags, designed expressly to localize the effect of a shell bursting in any one portion. Practically every man in this particular section of trench was either killed or wounded, but the rest of the line did not suffer. But the German gunners, having found their target, and having presumably observed their direct hit upon it, had their direction and range exactly, and they proceeded to pound that portion of the trench to pieces, and to make it a matter of desperate hazard for any man to cross the zone covered by their fire. The zone, of course, had to be crossed, the only other alternative being to climb out of the trench and run across the open until the further shelter was reached. There was a still greater hazard attached to this, for the open ground in this locality--as the officers knew--was visible to the German lines, and would expose the men, immediately upon their showing above ground, to a certain sweeping torrent of shrapnel, of machine-gun and rifle fire. So the portion of the battalion which was making its way down that communication trench was set to run the gauntlet of the smashed-in trench, and the shells which continued to arrive--fortunately--with almost methodical punctuality. The procedure adopted was for the end of the line to halt just short of the fire zone, to wait there, crouched low in the bottom of the trench, until a shell had burst, then to rise and run, scrambling and climbing over the fallen débris, into the comparative safety of the unbroken trench beyond, until the officer who was conducting the timing arrangements thought another shell was due to arrive, and halted the end of the line to wait until the next burst came, after which the same performance was repeated.