managed to give temporary treatment, so as to stop the bleeding. The poor fellow waved his hand to Tom as he was being taken away on a stretcher to the nearest field hospital for treatment.

"Here, let me have a look at that left arm of yours, Raymond, while I'm about it," said the surgeon, noticing that the pilot kept wiping drops of blood from his fingers with a handkerchief that had begun to assume a gory appearance.

This satisfied Tom, and the wound was speedily attended to, a bandage being bound in place. The only thing that was troubling the young airman was a haunting fear that he might be kept out of the fighting for several days; and at this exciting stage of the advance that would seem like a real calamity to so ambitious a pilot.

"I suppose you'd kick like a steer," said the surgeon, with a smile, "if I advised you to keep quiet for a day or two, because I know your breed; but if you must join in, be easy on that arm, Raymond. It might give you some trouble if inflammation should set in."

"Oh, I've had much worse scratches than that and never been laid up, Doctor," Tom remarked with the assurance that goes hand in hand with youth and abounding good health. "But I will favor it all I can. Couldn't keep me out of this riot unless you chained me to earth. There's something that keeps calling me up there, some thing that's mighty hard to resist."

"Yes, I know. You're all alike, you daring air pilots," said the other, shaking his head disapprovingly. "But you're splendid, splendid! And I'm certainly proud to be an American these days. You boys have set a pace that every British and French aviator will have to hustle to equal. Your coming has been the turning point of the war. The Hun is already whipped, only he doesn't wholly realize it just yet."

Tom, instead of seeking his quarters at once for rest, "loafed around" watching all that went on. Never a plane that came back but he was there to receive the comrade with enthusiasm. Some had been in the fight and bore signs of the experience through which they had passed. One especially was burning with disappointment because he had lost his "prize."

"Had him going, too, when this motor of mine went back on me and started in to miss fire so often that he got away," he spluttered. "Never was so mad in all my life as when I had to turn and sneak back home like a dog with his tail between his legs. But me for another machine, and back to the game again. I'll get that Hun yet, see if I don't!"

Often did Tom strain his eyes trying to pick out the plane of his chum among those that from time to time could be seen far distant, some engaged with the enemy, while others were seeking to gain information of value to the American commander.

When a whole hour had gone and there was still no sign of Jack, he began to feel worried. Vainly he questioned some of the returning pilots; for as the battle waned both above and below they were now coming in by shoals, tired, yet full of enthusiasm over their recent exploits.

From one Tom managed to secure the only tip that seemed of value; and it was hardly encouraging.

"I am sure I saw Jack having a lively circus with several Boches about an hour back," this man informed Tom. "Don't know how the jig ended, because I found myself in a mix-up soon afterwards, and it kept my hands full. But let's hope the boy came through O K. I saw you drop your man, Tom; and it must have been a close shave for you in the bargain."

The man went on about his business, and Tom again took up his weary watching and waiting. The minutes dragged by, but still no Jack, nor did there come any further word of him. Finally, weary and discouraged, Tom turned back toward his temporary quarters.

On arriving there, however, he found something that for the moment took his mind off the uncertain fate of his chum.

CHAPTER III

JACK'S STRANGE FIND

"Letters!" exclaimed Tom, as he entered the building where he had his headquarters. "One for me from home, and two for Jack," he went on, as he hurriedly sorted the little pile.

"Nice!" was his next ejaculation, as he looked at the postmark on the next letter he picked up. "Who is writing to me from Nice? I don't know anybody in the south of France."

The next letter he picked up was also postmarked "Nice." This one was addressed to Jack Parmly, was more than twice the thickness of the one addressed to Tom, and was in the same girlish handwriting.

"Bessie Gleason!" This was Tom's third exclamation. Then he slit the envelopes of his letters one after another and sat down to read his mail.

While he is engaged in this apparently pleasing occupation, and at the same time keeping an anxious eye out for the coming of his chum, Jack, it might be just as well to explain a little further who these daring young American air pilots were, and also tell something concerning their previous exploits.

Tom Raymond and Jack Parmly had both been born in Virginia, and there, at a government school for aviation training, they had taken their first lessons in flying, after the world war broke out. They decided to follow that calling in case the United States should be eventually swept into the war.

Tom's father was an inventor whose secret papers concerning a wonderful airplane stabilizer had been stolen by an adroit German spy. Afterwards the two chums when in France had managed to recover these documents, as well as accomplish many other brilliant exploits, all this being told in the first volume of this series, entitled: "Air Service Boys Flying for France; or, The Young Heroes of the Lafayette Escadrille."

In the second volume Tom and Jack proved their right to be called first-class air pilots by battling with success against Hun fliers. They saw considerable of the tragic happenings that convulsed that portion of France, while they were connected with the famous French flying corps.

Here, too, these young Air Service boys again found an opportunity for proving their worth in the rescue of pretty Bessie Gleason and her mother from an old chateau in Lorraine where Carl Potzfeldt, a German spy, had them imprisoned. These interesting and exciting events will be found in the second volume of the series, entitled: "Air Service Boys Over the Enemy's Lines; or, The German Spy's Secret."

Then came another series of happenings that must always appeal to boy readers fond of thrilling scenes, for in the next book, among many other things, is told how Tom and Jack succeeded in silencing the monster cannon that from a distance of sixty miles and more was bombarding Paris. That will be found narrated in "Air Service Boys Over the Rhine; or, Fighting Above the Clouds."

Then there is the volume just preceding this, in which again the two brave young Yankee air pilots were given an opportunity to prove the value of their training, now in the service of the American forces, for General Pershing had come across the sea, and his army was beginning to make its presence felt at several sectors of the battleline.

What they saw and did, as well as vivid descriptions of the momentous events accompanying the great German drive is told in the fourth book of the series, "Air Service Boys in the Big Battle; or, Silencing the Big Guns."

Among their friends at the front was a young and daring aviator, Harry Leroy by name, who had had the misfortune to be shot down behind the German lines, and it was in connection with his discovery and rescue by the chums that some of the events of the last volume came about.