The Sergeant of engineers having completed his little lecture, with himself and his class still in this world, the soldiers and officers all withdrew to the end of the field, some 200 yards behind the trench, and there lay down on their stomachs. I got into the trench with the engineer, placing myself to his left in front of the entrance to the bomb-proof, and the demonstration in the gentle art of grenade-throwing began. He took bomb number one, stuck the pin at the end of the cord firmly into the hole, swung his arm back and let fly. Having seen the departure of the bomb, I ungracefully tumbled into the bomb-proof, with the engineer a close second. Once there, there was an appreciable pause. Then came an explosion, the violence of which really astonished me. I could distinctly feel the ground shake. After giving the fragments which had been hurled our way plenty of time to come down on the roof, we stepped out into the trench again. The engineer next picked up bomb number three with the deal handle, hammered the nail home with one sharp rap against the edge of the trench and sent the grenade hurtling through the air. The mechanism of the first bomb had not been put in operation until the bomb started on its flight. But the fuse of this third bomb started burning the instant he hammered the nail in, and was burning while he was whirling his arm preparatory to letting it fly. As it thus got a running start on us, we had only barely time to get under cover before the explosion took place. Next came bomb number four. The demonstrator adjusted the black band round his left thumb, took the bomb in his right hand and gave it a scratch. He evidently had some doubts as to whether the first scratch had lighted the fuse, because after glancing at it he proceeded to give it a second scratch before throwing it. I need hardly say that I had already made home base in the bomb-proof and was perfectly satisfied to watch from there his second effort to get a light, which was crowned with complete success. After watching the way these three bombs were started and thrown I now wanted to watch the rest of them explode. So after considerable discussion between the staff-officer who had me in charge and the officer of explosives as to just how much danger there was in the operation, we moved out of the trench up to the top of a little rise about fifty yards to the right, where we ensconced ourselves in some bushes. The soldiers were all kept at their original distances of 200 yards behind the trench.