Our greatest trial was the canister. It was a two-gallon drum with a cylinder inside containing about two pounds of an explosive called ammonal that looked like salmon paste, smelt like marzipan, and when it went off sounded like the day of judgment. The hollow around the cylinder was filled with scrap metal apparently collected by the French villagers behind the German line—rusty nails, fragments of British and French shells, spent bullets, and the screws, nuts, and bolts that heavy lorries leave behind on the road. We dissected one canister that had not exploded and found in it, among other things, the cog-wheels of a clock and half a set of false teeth. The canister was easy to hear coming and looked harmless in the air, but its shock was as shattering as the very heaviest shell. It would blow in any but the deepest dug-outs; and the false teeth and cog-wheels and so on would go flying all over the place. We could not agree how a thing of that size was fired. The problem was not solved until 1st July, when the battalion attacked from these same trenches and found one of the canister-guns with its crew. It was a wooden cannon buried in the earth and fired with a time-fuse. The crew offered to surrender, but our men refused; they had sworn for months to get the crew of that gun. One evening I was in the trench with Richardson and David Thomas (near ‘Trafalgar Square,’ should anyone remember that trench-junction) when we met Pritchard and the adjutant. We stopped to talk. Richardson complained what a devil of a place it was for trench-mortars. Pritchard said: ‘That is where I come in.’ He was the battalion trench-mortar officer and had just been given the first two Stokes mortar-guns that we had seen in France. Pritchard said: ‘They’re beauties. I’ve been trying them out and to-morrow I’m going to get some of my own back. I can put four or five shells in the air at the same time.’ The adjutant said: ‘About time, too. We’ve had three hundred casualties in the last month here. It doesn’t seem so many as that because we’ve had no officer casualties. In fact we’ve had about five hundred casualties in the ranks since Loos, and not a single officer.’ Then he suddenly realized that he had said something unlucky. David said: ‘Touch wood.’ Everybody sprang to touch wood, but it was a French trench and unriveted. I pulled a pencil out of my pocket; that was wood enough for me. Richardson said: ‘I’m not superstitious, anyway.’