From that hour on Jack continued in a fever of suspense. His one thought was of the coming of the official notification connected with their hoped-for leave.

Tom fancied that his chum did not get much sleep on the following night, the last both of them hoped they would have to spend in the dugout used as a billet back of the American front.

So another day found them. Jack took special delight in casting up figures connected with the case. These he would show to his chum, and make various comments. Tom, realizing how the other was endeavoring to suck consolation from this proceeding, encouraged him in it.

"By to-night," Jack said, more than once, "it will be three whole days since the steamer sailed from Havre. I've tried to find out how fast she is, and then figured that they'd have to slow down when passing through the barred zone. I reckon it will take her eight or nine days to get across."

"Oh, all of that," Tom assured him; "and it might be as many as twelve. You see, the few passenger steamers still in use haven't been in dry dock for the longest time, and their hulls must be covered with barnacles, which cuts off considerable from their speed."

Jack gave him a thankful look.

"You're the best sort of jollier, Tom," he observed. "You know how to talk to a fellow who's quivering all over with eagerness and dread. What if something happens to hold up those notices until it's too late for even Colin's big bomber to catch up with the steamer?"

"You're only borrowing trouble when you allow yourself to fear that," was the reply. "But all the same, I mean to do everything I can to get things hurried along. I'll see the general, and with your permission explain to him that there's great need of our getting word to-day."

"But, surely, you wouldn't dare hint anything about the big trip we want to take, Tom?" asked Jack, looking alarmed.

"I should say not!" came the immediate response. "If we did that, the general would consider it his duty to put his foot down on the mad scheme right away. Trust me to let him know we stand to lose out in something that concerns your whole future if the notifications are delayed beyond early this afternoon, and I'm sure he'll start the wires going to get them here."

"What can I be doing in the meanwhile?"

"You might see to making arrangements for crossing to the coast on the first train that goes out," answered Tom.

"But that's going to be slow traveling, even if we're lucky enough to get aboard," protested the other. "Tom, do you think the general would permit us to take our machine, and fly to Dunkirk?"

"Good! That's a clever idea you've hit on, Jack!" exclaimed the other. "I'll take it up with the general when I see him. He might find it convenient, you know, to have some message sent across the country to the coast; and it would save us hours of time, perhaps win the race for us. A splendid thought, Jack!"

"Then let's hope it can be carried through," returned the other.

Tom did not lose any more time but hurried away to try to get an opportunity to talk with the kindly old general. He had always shown an interest in the fortunes of the two Air Service Boys, and they had already received favors from him on several occasions.

The minutes dragged while he was gone. Jack could not keep still, so nervous did he feel, but continued walking up and down, "like a tiger in its cage," he told himself. He ran through the entire gamut of possible troubles and triumphs in his mind, as he tried to picture the whole thing.

"What great luck to have Colin Beverly break in on us just at the time when my fortunes had reached their lowest ebb," Jack kept saying to himself.

At last Tom came back. Jack could read success in his looks, even before the other had had a chance to open his mouth and say a single word.

"It's all right then, I take it, Tom?" he exclaimed impulsively.

"Didn't have any trouble at all in interesting the general," replied the messenger joyfully. "He said he'd see to having an urgent call go out to hurry the notifications along, and almost promised they'd get here by two this afternoon."

"And how about the plane business?"

"That's all settled in the bargain. I have written permission to make use of our plane, turning it over to a certain agent in Dunkirk after we've arrived there. The general will send a message over to us which we're to deliver at the same time we give up the machine."

"Great work, Tom! I've always said you'd make a mighty fine diplomatic agent, if ever you tried, and now I know it."

"No soft-soap business, please. If it had been anybody but the general I'd have surely fallen down on my job. But you know he's always had an interest in us, Jack."

"Do you think he suspected anything?" asked the other.

"Sure he did, but not the thing, for nobody in the wide world would ever dream we were planning such an unheard of thing as a non-stop flight across the Atlantic."

Tom dropped his voice to a whisper when he said this; not that there seemed to be any particular need of caution, but simply on general principles. They could not afford to take any chance of having their great plan discovered in these early stages of the game.

"Well, I don't know how I'm going to hold out much longer," complained Jack. "I can't keep still five minutes, but have to jump up and walk it off. Let's see—two o'clock you said, didn't you? That'll be nearly three long hours more. It's simply terrible, Tom! Sixty minutes in each hour!"

"But then we'll have to eat our regular midday meal, remember," Tom tried to cheer his companion up by saying. "If you prefer it, we might walk over to the field-hospital, which, by the way, I hear is to be moved ahead to-night, to keep in closer touch with the wounded straggling back from the front. The Y hut's close by, too, and we'd enjoy an hour or so with the girls. Nellie told me she expected her brother, Harry, to be back on our sector any day now, and if he should come before we clear out we'd be mighty glad to see him."

Jack hesitated.

"Gee! you do tempt a fellow, Tom," he finally remarked, as though coming to a conclusion. "Nothing I'd like better than to chat with Bessie and have a few of those Salvation Army girls' doughnuts to munch. But I guess it would be foolish in our laying off just now."

"You mean the notifications might arrive while we were gone?" remarked Tom, nodding his head, pleased because the other took such a sensible view of the matter.

"Yes. We might lose a whole hour, perhaps two, by being away," explained Jack. "That would be too bad; it might even turn out a catastrophe, if in the end that hour would save us from being beaten in the race against time."

"All right, then, we'll hang around and watch for something to come from Headquarters. The general promised me he'd have the notifications sent over without any delay just as soon as they came."

"Let's go over to the flying field and watch some of the boys come in," suggested Jack, and to this the other readily assented.

Even when an airman is off-duty his special delight lies in "hanging out" at the aviation field, seeing his fellow workers go forth, watching their return, and listening to the many thrilling accounts of battles fought, as well as perils endured.

The fascination of the sport, once it has fairly gripped a man, makes him its slave; he can think of little else; and doubtless even in dreams he fancies himself performing unusual hazards and earning the applause of the multitude.

However this proved to be a very good panacea for Jack's nervousness and they managed to put in a full hour there. Business was unusually brisk in the way of engagements; and Tom more than once secretly regretted that circumstances beyond their control caused them to miss a "whole lot of fun."

The enemy was up in the air in more ways than one on that day. Desperation on account of the blowing up of the bridge caused the German plane scouts to meet the challenges offered by the exultant Yankees, and news of many an encounter kept coming in about the time the two boys thought of leaving the field and going for their dinner.

Word had also been received of several accidents to American pilots, and it looked as though the history of that eventful day would set a new high-water mark in the way of losses.

Jack even began to fear they might be ordered to go up, which would bring about a fresh delay while communication was being established with Headquarters to verify their story. So he was really glad when Tom drew him away by suggesting that it was time they dined.

At one o'clock they were at their headquarters, killing time and waiting. Jack's nerves once more began showing signs of being frayed, or "ragged," as he called it. He jumped at the least unusual sound, and alternately looked expectant and despairing.

It was now close to two o'clock, and as yet there was no sign of relief. Jack jumped up for the twentieth time and started to walk back and forth, while others among the airmen were gathering their belongings together, preparatory to a change of base.

Then a messenger was seen hurrying toward them. Jack became almost wild with excitement, until he knew for a fact the notifications had arrived.

"And now," said Tom, "let's put for the field and get away without any further loss of time. It's a long way to Dunkirk, remember, even by way of the air line, as a bee would take it. And we must get there before dark!"

They ran part of the way, and thus presented themselves before the hangar. Ample preparations had already been made. The petrol tank had been filled, and, everything being in readiness, they would have nothing to do but jump aboard and make a quick start.

But Tom was too old a pilot to take things for granted. After that recent experience with treachery he meant to be doubly careful before risking their lives in the air. Dunkirk on the Channel was a considerable distance off; and a drop when several thousand feet above French soil would go just as hard with them as if it were German territory.

Accordingly he took a survey of the plane from tip to tip of the wings; looked over the motor, tested every strut and stay, leaving nothing to Jack, who was fairly quivering with the intensity of his feelings.

Even the longest day must come to an end, and Tom's examination was finally completed.

"Get aboard!" he told Jack. "We're in great trim to make a record flight of it. And even the breeze favors us, you notice."

"Let's hope it keeps on as it is," said Jack, quickly; "because an easterly wind will help carry us on our way to-night!"

"We'll be in luck to have such help," Tom replied. "As a rule, the passage from Europe to America meets with head winds most of the way. How are you fixed, Jack?"

"All ready here, Tom."

"Half a minute more, and I'll be the same. Take your last look for some time, Jack, at the American fighting front. We'll never forget what we've met with here, and that's a fact."

"But, Tom, we expect to come back again, if all goes well," expostulated Jack. "In fact, we've just got to, or be accused of running away. We arranged all that, you remember, and how we'd manage to get across in such a way that no one will be any the wiser for our having been out of France."

"Don't let's worry about that yet," said Tom. "The first big job is to get across the Atlantic. Ready, back there? Here goes!"

Another minute, and with a rush and a roar the plane sped along the field, took an upward slant, and set out for the coast. The first leg of the great flight had actually been started!