Up at the observation post things are very different. There the observing officer sits, watching the black and yellow smoke clouds of the bursting high explosive, or the cotton-wool-like puffs of the shrapnel. "No. 1 fired, sir!" The words of the telephonists seem to come as from some other world. Here she comes, far away behind, the whistle of the shell shrieking louder as she passes right overhead--splendid! in the very trench itself; see the black smoke spread out and rise slowly from a long section of trench, whilst the green vegetation grows white with the falling chalk. No correction can be made to that, "No. 1, repeat!" "No. 2 fired, sir!" Here she comes, ah, a little to the right--"No. 2, ten minutes more left, fire!" So it goes on, until this particular section of trench has practically disappeared, leaving only a white scar. Then a change of target and a repetition of the destruction. A fascinating business this on so fine an autumn day, so fascinating that all sense of time is lost, all conjecture as to whether the enemy will take it into his head to select our observation post as a target is forgotten. The only thing in the world is the measured fall of the shell and the swift framing of the consequent order, the only pleasure the deep satisfaction of a well-placed round, the only despair the haunting memory of a shot wasted that might have been saved by a different procedure. During those four days of ceaseless bombardment, the enemy made very little reply except at certain points; we subsequently discovered why. He made no attempt to distribute his fire along our front line, nor did he make a systematic search for our observation posts, the vital organ of every battery and its most vulnerable one. Certain spots he selected, and with magnificent gunnery rendered them utterly untenable. Shell after shell fell with mathematical accuracy into Vermelles, Le Rutoire, Quality Street, but when once we had learnt these favoured spots, our casualties were very few, being avoided by the simple expedient of removing to places that appeared to be more suitable in the capacity of health-resorts, or, where that was impossible, taking to the cellars and remaining there.