"I think you're right," he answered. "Well, here's the plan. There's a deep ravine that runs clear across the frontier. I spent an hour in it. They've built a plank bridge across the top just this side of the line, and the patrol comes to the ravine about every three minutes. It is practically impossible to get out of sight and sound along that ravine in three minutes, but ..." "Unless we could drar the patrol's attention away!" said Sapper Maggs. But Francis ignored the interruption. "... We can at least try it. Come on, we must be starting! Thank God, there's no moon; it's as dark as the devil outside!" We roused up Monica and groped our way out of the cave into the black and dripping forest. Somewhere in the distance a faint glare reddened the sky. From time to time I thought I heard a shout, but it sounded far away. We crawled stealthily forward, Francis in front, then Monica, Maggs and I last. In a few minutes we were wet through, and our hands, blue and dead with cold, were scratched and torn. Our progress was interminably slow. Every few yards Francis raised his hand and we stopped. At last we reached the gloomy glade where, as Francis had told us, according to popular belief, the wraith of Charlemagne was still seen on the night of St. Hubert's Day galloping along with his ghostly followers of the chase. The rustling of leaves caught our ears; instantly we all lay prone behind a bank. A group of men came swinging along the glade. One of them was singing an ancient German soldier song: "Die Vöglein im Walde Sie singen so schön In der Heimat, in der Heimat, Da gibt's ein Wiederseh'n." "The relief patrol!" I whispered to Francis, as soon as they were past. "The other lot they relieve will be back this way in a minute. We must get across quickly." My brother stood erect, and tiptoed swiftly across Charlemagne's Ride, and we followed. We must have crawled for an hour before we came to the ravine. It was a deep, narrow ditch with steep sides, full of undergrowth and brambles. Now we could hear distinctly the voices of men all around us, as it seemed, and to right and to left and in front we caught at intervals glimpses of red flames through the trees. We could only proceed at a snail's pace lest the continual rustle of our footsteps should betray us. So each advanced a few paces in turn; then we all paused, and then the next one went forward. We could no longer crawl; the undergrowth was too thick for that; we had to go forward bent double. We had progressed like this for fully half an hour when Francis, who was in front as usual, beckoned us to lie down. We all lay motionless among the brambles. Then a voice somewhere above us said in German: "And I'll have a man at the plank here, sergeant: he can watch the ravine." Another voice answered: "Very good, Herr Leutnant, but in that case the patrols to right and left need not cross the plank each time; they can turn when they come to the ravine guard."