12.25--the scout bent his eyes on the ground. A couple of minutes later a handful of white cottages flitted past as he looked down between his feet. His enemy could not be seen. The body of the monoplane hid him as he flew below and slightly in rear, but the roar of his engine, louder than the scout's own, could just be heard. Now was the time--the scout turned off abruptly at a tangent along the line he had marked out for himself and drove his engine at its fastest. The speedometer needle oscillated over 101 miles an hour. He calculated that he had approximately twenty miles to go ere he reached the patch of country he wished to explore. He should reach the commencement of the enemy's left flank at 12.39, and be able to spend six minutes in flying over five miles of ground and then have a couple of minutes in hand. To the trained intellect behind his keen eyes six minutes were amply sufficient. Having run along the left flank it was simplicity itself to turn to the right and glide down into his own lines. There seemed nothing to stop him. The pursuing machine was being quickly left behind. The slow biplane now far off to his right could not possibly arrive in time. The sky in front was clear of any menace. Again he began to draw close to the great belt of dust-cloud which stretched out to his right and again the din of battle began to overpower the roar of his engine. Directly ahead was a dark mass of woodland. It was from thence that the enemy's screen around the right flank of the scout's army commenced. He swerved slightly to the left, behind it. The hour was a second or two over 12.38. Below him was a network of country roads, and from four strands of that network which ran in an approximately parallel direction, coincident with his own course, arose long dense clouds of dust. It was the dust of marching columns. The scout shot a glance back at his pursuer, assured himself that it was five or six miles in rear, and slowed down his engine as he entered upon a long, gradual descent over the route of those marching columns.