I was proceeding like an automaton along the trench when suddenly I came upon an officer who, I afterwards found out, was going up to fix his next gun positions. He was sitting on a sandbag swearing like Hades, and trying to disperse the clouds of flies which were settling upon him. He looked up as I approached, then suddenly burst into a peal of laughter. I stood still and grinned, not daring to open my mouth to laugh for fear of losing my cigarettes. Then I dropped my tripod and leaned against the trench side to rest. His laughter suddenly developed into a coughing and spluttering, spitting and swearing, which in itself was strong enough to drive all the flies in existence away. "Bust the things!" he spluttered. "I got a mouthful of them! They might have just come off some dirty Bosche. Got a drink on you?" "Yes," I said, and handed him my water-bottle. He rinsed out his mouth. "I do believe it's worth risking shrapnel rather than tolerate these vile things!" he remarked. "But excuse my laughter; you did look funny coming along there." "Yes, I expect I did," I said, still puffing away at my cigarettes. "I'd smoke a dozen at once if I could. Anything to keep the flies away." "Well," he said, "I'm stumped. Have you one to spare?" I handed him my case. He lighted up and both of us, puffing as hard as we could, made quite a healthy volume of smoke. From above it must have looked as if a small fire was raging. We had sat there alternately puffing and chatting and killing flies by the hundreds for about ten minutes. I told him I wanted to get some scenes of Trones. He politely told me I ought to have brought my keeper out with me, but as he was going in that direction he would help me on the way to being killed by carrying my tripod. We started off. The shelling was getting unpleasantly near. Phoot-bang! We both ducked, my head getting a nasty knock against the tripod top. For the moment I thought I had been struck by the whizz-bang. Presently we reached a junction in the trench, and as my friend's road lay in an opposite direction we parted, and I trudged on alone. I was brought to a standstill by a mound of earth which completely blocked the way. By all appearances the shell that had caused it could have only come over a few minutes before, for a thin wisp of smoke was still curling up from the débris. "Well," I thought, placing my kit on the ground, "it's got to be done; so over I go." Here the air was completely free from flies. Evidently the gas from the bursting shell had choked them off for a time. Jove! I was glad. It was like heaven; and my tongue was beginning to burn rather badly through fiercely smoking two cigarettes at once.