This morning, however, he took no thought of the matter. Before taking off Major Cowan had said no more than, "Look sharp when we get south of la Chapelle; head on a pivot, you know." Shucks! Slim chance for any excitement with a group like this. Even if they sighted a small enemy patrol they would have to go merrily on their way and leave the game to someone else. However, a war pilot with skill enough to become such an ace as Larkin needs little caution about "looking sharp." It is habit with him, and those who fail to develop the habit are only a few hours or days removed from sudden disaster. There was little enough to see. They were flying westward. Again and again Larkin turned his head around, closed one eye and placing a thumb close to his open eye squinted into the blinding sun. Many times, by the employment of that little trick, he had been able to momentarily diffuse the sun's rays sufficiently to catch the faintest blurred outline of enemy planes sitting in the sun and waiting for the proper moment to dive. This morning the sun seemed unusually bright and blinding. Somewhat ahead, and to the south, three large French observation planes were coming up toward the lines at la Chapelle. They were just about even, vertically, with the cloud bank over the Surmelin Valley. They would pass almost directly under the bottom flight, led by Yancey. Larkin watched them, somewhat idly. Photographic mission, probably. Then, with little or no interest in them, his eye ran along the two converging lines of planes that made up Yancey's flight. That moment he noticed McGee's plane cut out of position and zoom up at an angle too steep to be maintained. Then McGee's plane levelled off and was hurled through a series of quick acrobatics. It meant but one thing--manoeuver! Larkin jerked his head around and squinted into the sun. Not a thing there--at least nothing he could see--and as soon as the stabbing streaks of light left his eyes he glanced toward the cloud bank over the Marne. Nothing there. The three French observation busses, far below, were going gaily on their way. But McGee was still climbing and stunting. Larkin knew that this was no idle exhibition. McGee didn't fly that way. He was trying to draw their attention to something. Larkin looked ahead at Cowan's plane. That moment the Major dipped his plane twice. Now what in the world did he mean by that? Larkin wondered. Merely that he had noticed McGee and was on the alert? Or did he mean that he too had seen the enemy? Enemy! Where was the enemy? Again Larkin turned his head to try the sun. Nothing there ... yes, by George! there was a blur of black spots. But it was such a fleeting view that he could not be sure, and tried again. Blast the sun! It made him blind as a bat!