But we had a bad time, as every one did. After a stiff three weeks of holding a nasty bit of the line, much digging of assembly trenches, and carrying in the mud, we took our part in a great battle. I shall not tell you about it (it is in the histories); but it was a black day for the battalion. We lost 400 men and 20 officers, more than twice the total British casualties at Omdurman. Hewett was killed and six other officers, the Colonel and twelve more were wounded. Eustace showed superb courage with a hideous wound. Harry and myself survived. Now I had made a mistake about Harry. After that scouting episode at Souchez I told myself that his 'nerve' was gone, that for a little anyhow he would be no good in action. But soon after we got to the Somme he had surprised me by doing a very good piece of work under fire. We were digging a new 'jumping-off' line in No Man's Land, two hundred men at work at once. They were spotted, the Boches dropped some Minnies about, and there was the beginnings of a slight stampede--you know the sort of thing--mythical orders to 'Retire' came along. All Harry did was to get the men back and keep them together, and keep them digging: the officer's job--but he did very well, and to me, as I say, surprisingly well. The truth was, as I afterwards perceived, that only what I may call his 'scouting' nerve was gone. It is a peculiar kind of super-nerve, as I have tried to show, and losing it he had lost a very valuable quality, but that was all at present. Or I may put it another way. There is a theory held among soldiers, which I will call the theory of the favourite fear. Every civilian has his favourite fear, death by burning or by drowning, the fear of falling from a great height, or being mangled in a machine--something which it makes us shiver to think about. Among soldiers such special fears are even more acute, though less openly confessed, but in the evenings men will sometimes lie on the straw in the smoky barns and whisper the things of which they are most afraid. It is largely a matter of locality and circumstance. In Gallipoli, where the Turks' rapid musketry fire was almost incredibly intense and their snipers uncannily accurate, men would say that they hated bullets, but shell-fire left them unmoved. The same men travelled to France and found rifle fire practically extinct but gun-power increasingly terrible, and rapidly reversed their opinions. More often, however, there has been some particular experience which, out of a multitude of shocks, has been able to make a lasting impression, and leave behind it the favourite fear.