"Do you know her?" asked Jack.

"No. Wish I did, though."

Jack glanced quickly and curiously at his chum.

"Oh, you needn't think you're the only chap that has a drag with the girls," went on Tom. "Just because Bessie Gleason--"

"Cut it out!" exclaimed Jack. "Look, she acts as though she wanted to speak to us."

The military chauffeur had alighted from the machine and was talking to one of the French aviation officers. Meanwhile the girl, left to herself, was looking about the big aviation field, with a look of wonder, mixed with alarm and nervousness. She caught sight of Tom and Jack, and a smile came to her face, making her, as Tom said afterward, the prettiest picture he had seen in a long while.

"You're Americans, aren't you?" began the girl, turning frankly to them.

"I know you are! And, oh, I'm in such trouble!"

Tom stepped ahead of Jack, who was taking off his cap and bowing.

"Let me have a show for my white alley," Tom murmured to his chum.

"You've got one girl."

"You win," murmured Jack.

"Yes, we're from the United States," said Tom. "But it's queer to see a girl here--from America or anywhere else. How'd you get through the lines, and what can we do for you?"

"I am looking for my brother," was the answer. "I understood he was stationed here, and I managed to get pa.s.ses to come to see him, but it wasn't easy work. I met this officer in his motor car, and he brought me along the last stage of the journey. Can you tell me where my brother is? His name is Harry Leroy."

Torn said afterward that he felt as though he had gone into a spinning nose dive with a Boche aviator on his tail, while Jack admitted that he felt somewhat as he did the time his gasoline pipe was severed by a Hun bullet when he was high in the air and several miles behind the enemy's lines.

"Your--your brother!" Tom managed to mutter.

"Yes, Harry Leroy. He's from the United States, too. Perhaps you know him, as I notice you are both aviators. He told me if I ever got to France to come to see him, and he mentioned the names of two young men--I have them here somewhere--"

She began to search in the depths of a little leather valise she carried, and, at that moment, the military chauffeur who had brought her to the aviation field turned to her, and spoke rapidly in French.

She understood the language, as did Tom and Jack, and at the first words her face went white. For the chauffeur informed her that her brother, Harry Leroy, whom she had come so far to see, was, even then, lying dead or wounded within the German lines.

"Oh!" the girl murmured, her fare becoming whiter and more white.

"Oh--Harry!"

Then she would have fallen from the seat, only Tom leaped forward and caught her in his arms.

And while efforts were being made to restore the girl to consciousness, may I not take this opportunity of telling my new readers something of the previous books of this series, so that they may read this one more intelligently?

Torn Raymond and Jack Parmly, as related in the initial volume, "Air Service Boys Flying for France; or The Young Heroes of the Lafayette Escadrille," were Virginians. Soon after the great world conflict started, they burned with a desire to fight on the side of freedom, and it was as aviators that they desired to help.

Accordingly they went to an aviation school in Virginia, under the auspices of the Government, and there learned the rudiments of flying.

Tom's father had invented an aeroplane stabilizer, but, as told in the story, the plans and other papers had been stolen by a German spy.

Tom and his chum resolved to get possession of the doc.u.ments, and they kept up the search after they reached France and were made members of the Lafayette Escadrille. It was in France that they met Adolph Tuessing, the German spy.

The second volume, ent.i.tled "Air Service Boys Over the Enemy's Lines; or The German Spy's Secret," takes the two young men through further adventures. They had become acquainted on the steamer with a girl named Bessie Gleason and her mother. Carl Potzfeldt, a German sailing under false colors, claimed to be a friend of Bessie and her mother, but Jack, who was more than casually interested in the girl, was suspicious of this man. And his suspicions proved correct, for Potzfeldt had planned a daring trick.

After some strenuous happenings, in which the Air Service Boys a.s.sisted, Bessie and her mother were rescued from the clutches of Potzfeldt, and went to Paris, Mrs. Gleason engaging in Red Cross work, and Bessie helping her as best she could.

Immediately preceding this present volume is the third, called "Air Service Boys Over the Rhine; or Fighting Above the Clouds."

By this time the United States had entered the great war on the side of humanity and democracy.

Then the world was startled by the news that a great German cannon was firing on Paris seventy miles away, and consternation reigned for a time. Tom and Jack had a hand in silencing the great gun, for it was they who discovered where it was hidden. Also in the third volume is related how Tom's father, who had disappeared, was found again.

The boys pa.s.sed through many startling experiences with their usual bravery, so that, when the present story opens, they were taking a much needed and well-earned rest. Mr. Raymond, having accomplished his mission, had returned to the United States.

Then, as we have seen, came the news of the arrival of the first of Pershing's forces, and with it came the sad message that Harry Leroy, the chum of Torn and Jack, had fallen behind the German lines. And whether he was alive now, though wounded, or was another victim of the Hun machine guns, could not be told.

"Harry's sister couldn't have come at a worse time," remarked Tom, as he rejoined Jack, having carried the unconscious girl to the same hospital where Du Boise lay wounded.

"I should say not!" agreed Jack. "Do you really suppose she's Harry's sister?"

"I don't see Any reason to doubt it. She said so, didn't she?"

"Oh, yes, of course. I was just wondering. Say, it's going to be tough when she wakes up and realizes what's happened."

"You bet it is! This has been a tough day all around, and if it wasn't for the good news that our boys are in France I'd feel pretty rocky. But now we've got all the more incentive to get busy!" exclaimed Tom.

"What do you mean?"

"I mean get our machines in fighting trim. I'm going out and get a few Germans to make up for what they did to Harry."

"You're right! I'm with you! But what about what's her name--I mean Harry's sister?"

"I didn't hear her name. Some of the Red Cross nurses are looking after her. They promised to let me know when she came to. We can offer to help her, I suppose, being, as you might say, neighbors."

"Sure!" agreed Jack. "I'm with you. But let's go and--"

However they did not go at once, wherever it was that Jack was going to propose, for, at that moment, one of the Red Cross nurses attached to the aviation hospital came to the door and beckoned to the boys.

"Miss Leroy is conscious now," was the message. "She wants to see you two," and the nurse smiled at them.

Tom and Jack found Miss Leroy, looking pale, but prettier than ever, sitting up in a chair. She leaned forward eagerly as they entered, and, holding out her hands, exclaimed:

"They tell me you are my brother's chums! Oh, can you not get me some news of him? Can you not let him know that I have come so far to see him? I am anxious! Oh, where is he?" and she looked from Tom to Jack, and then to Tom again.

CHAPTER III. ANXIOUS WAITING

Nellie Leroy--for such the boys learned was her name--broke the silence, that was growing tense, by asking: