Not until a day or so later, when Jack was able to sit up in bed and greet Tom with rather a pale face, did the latter learn all that had happened. And it was a very close call that Jack had had.

As Tom had guessed, it was some of the bullets from the Hun machine gun that had stricken down his chum. One had struck him a glancing blow on the head, rendering Jack unconscious and sending him down, a crumpled-up heap in the cockpit of his machine. Another bullet, coming through the machine later, had found lodgment in Jack's leg, cutting part way through the wall of one of the larger arteries.

It was certain that this bullet, the one in the leg, came after Jack was hit on the head, for that first wound was the only one he remembered receiving.

“It was just as though I saw not only stars' but moons, suns, comets, rainbows and northern lights all at once,” he explained to his chum.

The bullet in the leg had cut only part way through the wall of an artery. At first the tissues held the blood back from spurting out in a stream that would soon have carried life with it. But either some unconscious motion on Jack's part, or a jarring of the plane, broke the half-severed wall, and, just before Tom landed, his chum began to bleed dangerously. Then it was the surgeon had made his remark, and acted in time to save Jack's life.

“Well, I guess we made good all right,” remarked Jack, as his chum visited him in the hospital.

“I reckon so,” was the answer, “though the Huns haven't sent us any love letters to say so. But we surely did drop the packages in the prison camp, though whether Harry got them or not is another story. But we did our part.”

“That's right,” agreed Jack. “Now the next thing is to get busy and bring Harry out of there if we can.”

“The next thing for you to do is to keep quiet until that wound in your leg heals,” said the doctor, with a smile. “If you don't, you won't do any more flying, to say nothing of making any rescues. Be content with what you did. The whole camp is talking of your exploit. It was noble!”

“Shucks!” exclaimed Tom, in English, for they had been speaking French for the benefit of the surgeon, who was of that nationality.

“Ah, and what may that mean?” he asked.

“I mean it wasn't anything,” translated Tom. “Anybody could have done what we did.”

But of this the surgeon had his doubts.

In spite of the dangerous character of his wound, Jack made a quick recovery. He was in excellent condition, and the wound was a clean one, so, as soon as the walls of the artery had healed, he was able to be about, though he was weak from loss of blood. However, that was soon made good, and he and Tom, bidding farewell to their late comrades, returned to the American lines. They had been obliged to get an extension of leave—at least Jack had—though Tom could report back on time, and he spent the interim between that and Jack's return to duty, serving as instructor to the “huns” of his own camp. They were eager to learn, and anxious to do things for themselves.

Before long Jack returned, though he was not assigned to duty, and he and Tom visited Paris and told Nellie, Bessie and Mrs. Gleason the result of their mission.

“You didn't see Harry, of course?” asked Nellie, negatively, though really hoping that the answer would be in the affirmative.

“Oh, no, we couldn't make out any individual prisoner,” said Tom. “There was a bunch of 'em—I mean a whole lot—there.”

“Poor fellows!” said Mrs. Gleason kindly, “Let us hope that they will soon be released.”

“Tom and I have been trying to hit on some plan to rescue Harry,” put in Jack. “And we'd help any others to get away that we could. But is isn't going to be easy.”

“Oh, I don't see how you can do it!” exclaimed Nellie. “Of course I would give anything in the world to have Harry back with me, but I must not ask you to run into needless danger on his account. That would be too much. Your lives are needed here to beat back the Huns. Harry may live to see the day of victory, and then all will be well.”

“I don't believe in waiting, if anything can be done before that.” Tom spoke grimly. “But, as Jack says, it isn't going to be easy,” he went on. “However, we haven't given up. The only thing is to hit on some plan that's feasible.”

They talked of this, but could arrive at nothing. They were not even sure—which made it all the harder to bear—that Harry had received the packages dropped in the prison camp at such risk. The only thing that could be done was to wait and see if he wrote to his sister or his former chums. Letters occasionally did come from German prisoners, but they were rare, and could be depended on neither as to time of delivery nor as to authenticity of contents.

So it was a case of waiting and hoping.

Jack was not yet permitted to fly, so Tom had to go alone. But he served as an instructor, leaving the more dangerous work of patrol, fighting, and reconnaissance to others until he was fit to stand the strain of flying and of fighting once more.

“Sergeant Raymond, you will take up Martin to-day,” said the flight lieutenant to Tom one morning. “Let him manage the plane himself unless you see that he is going to get into trouble. And give him a good flight.”

“Yes, sir,” answered Tom, as he turned away, after saluting.

He found his pupil, a young American from the Middle West, who was not as old as he and Jack, awaiting him impatiently.

“I'm to get my second wing soon, and I want to show that I can manage a plane all by myself, even if you're in it,” said the lad, whose name was Dick Martin. “They say I can make a solo flight to-morrow if I do well to-day.”

“Well, go to it!” exclaimed Tom with a laugh. “I'm willing.”

Soon they were in a double-seater of fairly safe construction—that is, it was not freakish nor speedy, and was what was usually used in this instructive work.

“I'm going to fly over the town,” declared Martin, naming the French city nearest the camp. “Well, mind you keep the required distance up,” cautioned Tom, for there was, a regulation making it necessary for the aviators to fly at a certain minimum height above a town in flying across it, so that if they developed engine trouble, they could coast safely down and land outside the town itself.

“I'll do that,” promised Martin.

But either he forgot this, or he was unable to keep at the required height, for he began scaling down when about over the center of the place. Tom saw what was happening, and reached over to take the controls. But something happened. There was a jam of one of the levers, and to his consternation Tom saw the machine going down and heading straight for a large greenhouse on the outskirts of the town.

“There's going to be one beautiful crash!” Tom thought, as he worked in vain to send the craft up. But it was beyond control.