As we passed along the straight canal from Le Recul to Princebourg many barges were in evidence. Those at the side of the canal were taken to be moored up, and those in the middle to be moving, though the slowness of their speed made it impossible to decide on their direction, for from a height of ten thousand feet they seemed to be stationary. About a dozen Hun machines were rising from aerodromes at Passementerie, away to the left, but if they were after us the attempt to reach our height in time was futile. Between Le Recul and Princebourg we dropped fifteen hundred feet below the three rear machines, which hovered above us. Though I was far from feeling at home, it was necessary to sweep the surrounding country for transport of all kinds. This was done almost automatically, since I found myself unable to give a whole-hearted attention to the job, while the infernal motif of the engine's rag-time drone dominated everything and invited speculation on how much lower we were than the others, and whether we were likely to reach a friendly landing-ground. And all the while a troublesome verse chose very inopportunely to race across the background of my mind, in time with the engine, each cut-out being the end of a line. Once or twice I caught myself murmuring-- "In that poor but honest 'ome, Where 'er sorrowin' parints live, They drink the shampyne wine she sends, But never, never can fergive." Slightly to the east of Princebourg, a new complication appeared in the shape of a small German machine. Seeing that our bus was in difficulties, it awaited an opportunity to pounce, and remained at a height slightly greater than ours, but some distance behind the bus that acted as rearguard to the party. Its speed must have been about ten miles an hour more than our own, for though the Hun pilot had probably throttled down, he was obliged to make his craft snake its way in short curves, so that it should not come within dangerous range of our guns. At times he varied this method by lifting the machine almost to stalling point, letting her down again, and repeating the process. Once I saw some motor transport on a road. I leaned over the side to estimate their number, but gave up the task of doing so with accuracy under the double strain of watching the Hun scout and listening to the jerky voice of the engine. As we continued to drop, the German evidently decided to finish us. He climbed a little and then rushed ahead. I fired at him in rapid bursts, but he kept to his course. He did not come near enough for a dive, however, as the rest of the party, two thousand feet above, had watched his movements, and as soon as he began to move nearer two of them fell towards him. Seeing that his game was spoiled the Boche went down steeply, and only flattened out when he was low enough to be safe from attack.