Close by, a few German prisoners performing sanitary duties under a guard.  They were men in God’s image, and they went about on the assumption that all the rest of the war lay before them and that there was a lot of it.  A General told us that he had mentioned to them the possibility of an exchange of prisoners, whereupon they had gloomily and pathetically protested.  They very sincerely did not want to go back whence they had come, preferring captivity, humiliation, and the basest tasks to a share in the great glory of German arms.  To me they had a brutalised air, no doubt one minor consequence of military ambition in high places.

Not many minutes away was a hospital—­what the French call an ambulance de premiere ligne, contrived out of a factory.  This was the hospital nearest to the trenches in that region, and the wounded come to it direct from the dressing-stations which lie immediately behind the trenches.  When a man falls, or men fall, the automobile is telephoned for, and it arrives at the appointed rendezvous generally before the stretcher-bearers, who may have to walk for twenty or thirty minutes over rough ground.  A wounded man may be, and has been, operated upon in this hospital within an hour of his wounding.  It is organised on a permanent basis, for cases too serious for removal have, of course, to remain there.  Nevertheless, these establishments are, as regards their staff, patients, and material, highly mobile.

One hospital of two hundred beds was once entirely evacuated within sixty minutes upon a sudden order.  We walked through small ward after small ward, store-room after store-room, aseptic operating-room and septic operating-room, all odorous with ether, and saw little but resignation, and not much of that, for patients happened to be few.  Yet the worn face of the doctor in charge showed that vast labours must have been accomplished in those sombre chambers.

In the very large courtyard a tent operating-hospital was established.  The white attendants were waiting within in the pallid obscurity, among tables, glass jars, and instruments.  The surgeon’s wagon, with hot-water and sterilising apparatus, was waiting without.  The canvas organism was a real hospital, and the point about it was that it could move off complete at twenty-five minutes’ notice and set itself up again in any other ordained location in another twenty-five minutes.

Another short ride, and we were in an aviation park, likewise tented, in the midst of an immense wheatfield on the lofty side of a hill.  There were six hangars of canvas, each containing an aeroplane and serving as a dormitory; and for each aeroplane a carriage and a motor—­for sometimes aeroplanes are wounded and have to travel by road; it takes ninety minutes to dismount an aeroplane.  Each corps of an army has one of these escadrilles or teams of aeroplanes, and the army as a whole has an extra one, so that, if an army consists of eight corps, it possesses fifty-four