I got back into the grass and made my way downstream. Sliding gently through the grass, I kept catching my feet in something hard that felt like roots; but there were no trees in the neighborhood. I reached down and groped in the grass and brought up a human rib. The place was full of them, and skulls. Stooping, I could see them, grinning up out of the dusk, hundreds of them. I learned afterwards that this was called the Valley of Death. Early in the war several thousand Zouaves had perished there, and no attempt had been made to bury them. After getting out of the skeletons, I scouted along downstream and presently heard the low voices of Germans. Evidently they had found the net and planned to get the messages first. Creeping to the edge of the grass, I peeped out. I was opposite the bottle trap. I could dimly make out the forms of two men standing on the nearer end of the plank bridge. They were, I should judge, about ten yards away, and they hadn't heard me. I got out a Mills, pulled the pin, and pitched it. The bomb exploded, perhaps five feet this side of the men. One dropped, and the other ran. After a short wait I ran over to the German. I searched him for papers, found none, and rolled him into the river. After a few days in the Quarries we were moved to what was known as the Warren, so called because the works resembled a rabbit warren. This was on the lower side and to the left end of Vimy Ridge, and was extra dangerous. It did seem as though each place was worse than the last. The Warren was a regular network of trenches, burrows, and funk holes, and we needed them all. The position was downhill from the Huns, and they kept sending over and down a continuous stream of "pip-squeaks", "whiz-bangs", and "minnies." The "pip-squeak" is a shell that starts with a silly "pip", goes on with a sillier "squeeeeee", and goes off with a man's-size bang. The "whiz-bang" starts with a rough whirr like a flushing cock partridge, and goes off on contact with a tremendous bang. It is not as dangerous as it sounds, but bad enough. The "minnie" is about the size of a two-gallon kerosene can, and comes somersaulting over in a high arc and is concentrated death and destruction when it lands. It has one virtue--you can see it coming and dodge, and at night it most considerately leaves a trail of sparks. The Boche served us full portions of all three of these man-killers in the Warren and kept us ducking in and out pretty much all the time, night and day. I was lucky enough after the first day to be put on sappers' duty. The Sappers, or Engineers, are the men whose duty it is to run mines under No Man's Land and plant huge quantities of explosives. There was a great amount of mining going on all the time at Vimy Ridge from both sides.