Once sighted by allied pilots, Hal knew, and there would be trouble. Any plane approaching from the direction of the German lines, and not in that section of the field designated as a safety zone by General Dupree, Hal was perfectly well aware, would incur the suspicion of whatever allied airman sighted it.

"He might let me explain, and he might not," the lad told himself. "Best way, I guess, is to keep out of their reach."

The lad made out the forms of several sky fighters several miles away. Of these he had no fear, however, for the distance was too great and they seemed, if anything, to be moving away from his machine. But soon the boy saw half a dozen craft, in close battle formation, bearing down on him.

"Here they come, ready for business," he muttered, "and they're Frenchmen, too, judging from here. Well, we'll have to go up a little higher and see if we can't dodge them."

The airplane went higher in the air.

But the craft bearing the German peace envoys had been sighted by the pilot of the air fleet, and the entire squadron now dashed toward Hal.

Came a rifle shot from the distance and Hal heard the whine of a bullet not a great distance from his ear.

"Too close for comfort," the lad muttered. "Now here is a case where I'm sorry the French air fighters are such confounded good marksmen. I'll have to see what this craft can offer in the way of speed."

The airplane seemed to leap forward as Hal touched the controls.

The machine bearing the lads and the German envoys was now many feet above the allied battle squadron. And, before the commander of the air flotilla realized what was happening, his prey sped by him unharmed.