"Not much chance of that if you feel like me. I couldn’t sleep a wink, though I’m tired enough." They sat down, took some chocolate from their tins, and prepared for their vigil. All was silent around them. There were no longer sounds of traffic; the roads had apparently diverged. The whole countryside lay peaceful under the silent stars. Time went on. The air was cold. Now and then they got up and tramped to and fro to stir their chilled blood. Ten o’clock: eleven: no sound. Kenneth looked at his watch at ever shorter intervals. He was becoming restless. Had they adventured on a vain quest? The moon crept above the horizon, dimly illuminating the landscape, showing here a dark rounded mass that must be a wooded hill, there the white walls of a solitary farmhouse. "There’s no getting back to-night," thought Kenneth, as the light increased. It was just past midnight. They were sitting side by side, silent, disappointed, depressed. "Hark!" said Harry suddenly. There was a low continuous rumble in the distance. It grew louder. They rose to their feet, and looked across the fields eastward. The ground stretched away in undulations, alternate dark and light bands in the moonshine. They could see nothing to explain the sound. It came from their right, increasing in volume as it approached, then diminishing as it passed away to the left, finally ceasing. "Sounded like a railway truck," said Harry. "There’s no line there," replied Kenneth. "The only line shown on the map is the one running through the village almost due east; it turns to the north-east after cutting the German lines. It must be a good three or four miles from here. That sound went right across our front, from south to north, and couldn’t have been more than half a mile away." "Well, it’s stopped now. We needn’t bother about it. Quite certainly it wasn’t made by the guns, and that’s the only riddle we’re called on to solve. I’m fed up with this, Ken." "So am I. The idea of a whole day here is sickening. Still, it can’t be helped." They sat down again, each thinking his own thoughts. Suddenly there was a momentary flash, instantly followed by a terrific roar. "The gun!" exclaimed Kenneth, springing up. "And jolly close, too," said Harry, looking across the fields. "Which side of us?" "I don’t know. We must wait for the next. This is getting exciting." Within a minute or two they saw the flash again, lighting up the sky behind a low ridge on their left front. The noise of the discharge reverberated and died away. "Come on!" whispered Kenneth. They crept along the hedge in the direction of the ridge. A third report rent the air; then, after a minute’s silence, they were surprised to hear a renewed rumbling, which passed across their front nearer than they had heard it before, and receded towards the south. "’Pon my word, it seems to have some connection with the gun after all," murmured Kenneth.