"Hard to beat," seemed to be the general verdict. "Fritz will have to open his eyes tomorrow."

And so the show above went on. A flock of little birds chirped and flopped past the group below. What pikers they seemed by comparison, with the show going on above — far above! And now they were descending in long spirals, each squad by itself, yet preserving the mathematical distance required, both from the opposing squad and at the same time keeping the line prescribed for such tactics during drills at the home grounds.

Particularly did Blaine distinguish himself in the daring of his stunts. Erwin was hardly behind him. They looped again, they rolled, they did the wing and tail slides, doing the last until they fell almost perpendicularly a thousand feet. Finally they righted hardly two hundred feet above the earth; then shot upward again at almost incredible speed.

And now the two leaders circled slowly as their respective squads followed on towards the ground, some falling, drifting like dead leaves, others slanting lazily as they passed the leaders, and on down, alighting at last each in his appointed place or thereabouts.

And then the two leaders began circling and swooping more and more rapidly until those below felt the whirring rush of air as the two planes swept by so low that one imagined that an arm would nearly touch them.

All hands knew it was rivalry — the rivalry of stunts. Yet to stand below and watch those steel engines falling down on you from the skies took the same kind of nerve to keep from dodging as only airmen themselves are gifted with by practice.

Finally all this drew to a close. The machines at last ranged themselves at opposite extremes of the landing stage and with a final swoop both were apparently upon the spectators as with the rush of a whirlwind. Yet, dizzy as it looked, it was mathematically timed. The two planes flattened as if by magic; they rose, dipped again and, passing each other in the down grade, saluted methodically as they passed the Commander. Ten seconds later their wheels dropped gently on the gravel at either end of the parade ground two tired looking aviators left their the waiting mechanics and walked soberly to the others.

The stunts were over for the day.

CHAPTER VI

CATCHING THB SPY