“Just in time to help me out in planning a bill of fare for supper, too,” Pudge told them. “There are some tinned meats here, but I’d prefer something good and warm.”

That difficulty was soon swept aside, for the others nominated several dishes they chanced to be exceedingly fond of, and Pudge found he was going to have his hands full preparing them with such limited accommodations.

However, willing hands make light work, and both Frank and Billy were ready to give him all the assistance required; so that in the end they had quite a feast spread upon the little drop-table that took up no space at all when not required for use.

It was a peculiar supper-setting, with only that one lantern to give them light. Of course they could have used the acetylene lamps, but their supply of carbide was rather low, and there could be no certainty about obtaining a further amount, so Frank thought it best to husband what they had.

The weird appearance of the big seaplane added more or less to the strangeness of their surroundings. Still, by this time, all of the boys had become so accustomed to seeing its bat-like wings, and the boat body with the spoon-shaped bow that they would have missed it had the hangar been empty.

Over the meal they chatted in low tones, discussing many things connected with their mission across the sea. Little was said concerning the contemplated dash laid out for the following morning, because in the first place they knew none of the particulars; and then again the raid was the Allies’ secret, not theirs.

The unexpected presence of that concealed spy had given them a rude jolt. They appeared to be living in an atmosphere of espionage; and somehow it seemed as though hostile eyes and ears might be close by, even though unseen.

When finally they were through, it was remembered that they had decided to give the chilled guards a treat; so Pudge brewed a copious amount of strong coffee that was of a rich dark color, and had the “odor of ambrosia,” as Billy called it.

“Since you’ve done so much, Pudge,” remarked Frank, “you’re going to be the one to go along with me on the rounds. So get that big tin cup, and we’ll carry the can of condensed Swiss milk with us. We might as well give them the coffee just as they fancy it, either black or with the fixings.”

Pudge beamed on his chum. Evidently he had not expected to be favored with an invitation like this; for as a rule he was apt to be left behind on account of his well-known clumsiness.

Frank, however, was wise enough to carry the steaming pot of coffee himself, as an insurance against spilling. If Pudge did happen to trip over some unseen obstruction and measure his length he could hardly do worse than spill the thick condensed milk, or dent the big tin cup.

So they started forth, and coming to the gate first of all surprised the two khaki-clad Tommies there. How eagerly they in turn quaffed the contents of that common tin cup can be imagined, for the night air was growing cold, and a dismal prospect stared them in the face.

Frank carried the lantern in one hand; it was in the dark of the moon, and he meant that none of the guards should make a mistake and fire upon them for unwelcome prowlers.

News of their coming was sent on ahead, each sentinel calling out to the next one; and in this way the boys made the complete rounds, neglecting none.

When they finally returned to the building it was with an empty pot, and the satisfaction of knowing they had done something to cheer up the brave fellows who were protecting their property.

Frank himself went the rounds of the hangar once more to make sure that everything was as it should be. There was a sense of responsibility resting on him that the others did not feel in the same degree, for Billy was one of those care-free individuals, and as for Pudge, did you ever know of a fat, good-natured boy worrying?

“I hope we don’t have any trouble between now and dawn,” Billy was heard to say as they began to get things ready for sleeping, each having a blanket, as well as some cushions with which to form a rude bed.

“Yes, because to-morrow ought to be a big day for the Sea Eagle Company, Limited,” added Pudge, swelling a little with pride as he pronounced that name. “In fact, it promises to eclipse anything we’ve ever stacked up against before in all our travels.”

“It was all very fine,” commented Billy, “to knock around the Moon Mountains in Africa, meeting up with wild beasts and wilder men; it was thrilling to be away down there in the frozen regions of the Antarctic; but let me tell you all those happenings rolled into one couldn’t equal a trip over the fighting lines of two great armies in a death grapple along the trenches.”

“I’m not going to get one wink of sleep this whole night, thinking about it,” asserted Pudge, shaking his head in a sad fashion; but somehow his threat did not seem to give either of his chums the slightest degree of anxiety, for they knew what an enormous propensity Pudge had for sleep.

It may have been about ten o’clock when they all lay down and tried to lose themselves in slumber. The lantern had been extinguished, but Frank had things fixed so that if any sudden necessity arose he could press a button that was close by his hand and illuminate the interior of the hangar with the searchlight connected with the seaplane.

Just as they expected, Pudge was breathing stertorously before seven minutes had crept by, proving his dismal foreboding to have been an empty threat. Billy was the next one to drop off; and finally Frank, too, lost track of things after he had tried various expedients in the hope of forgetting himself.

They were aroused by a sudden loud noise that sounded like an explosion. All of them sat upright as though brought in contact with a galvanic battery; but Frank desisted even when his hand was in the act of reaching for the button connected with the light.

If that had been a bursting bomb dropped by some hovering German Taube, for him to betray the exact position of the hangar by starting up the brilliant electric searchlight would be the height of folly.

“What could that have been, Frank?” Pudge was asking in trembling tones; for as it afterward turned out he had been having a weird dream, and his first thought on being so rudely aroused was that the top of a volcano he was exploring had been blown off by an eruption, sending him a mile high.

“The Germans have made a night raid, and are trying to smash the Sea Eagle, after seeing what she could do to their machines and dirigibles!” declared Billy, as if his mind had already been made up.

“Do you think so too, Frank; and are we apt to be blown up any second now by a better aimed bomb than that first one?” Pudge demanded, evidently trying hard to control himself, and show that he could face danger with an undaunted front.

Frank had had time to think. He realized that several things conflicted with such an explanation of the mysterious explosion. Voices, too, outside could be heard, and it was evident that the guards were calling to one another.

“On second thought,” Frank ventured to say, “I don’t believe that could have been a bomb. It didn’t make near enough noise, though perhaps we thought it pretty loud on being waked up so suddenly.”

“Then what could it have been, Frank?” demanded Billy.

“I’ve got an idea one of the guards may have fired at some prowler,” replied the other; “in a minute or so I’ll take the lantern and go out to see.”

He insisted on going alone, and the other two remained back of the barred door awaiting his report. Frank was gone about twenty minutes when his signal was heard on the other side of the door. Upon being admitted he at once eased their fears.

“After all, it was the discharge of a gun, just as we guessed,” he observed. “One of the guards believed he saw a shadowy figure creeping along. He challenged, and on hearing the bushes shake as the unknown started away, the sentry shot.”

“Perhaps, after all, it was a false alarm?” suggested Billy.

“No, it was a prowler, all right,” said Frank, “for the sergeant and myself went out to where he told us he had aimed, and we found not only footprints in the dirt, but specks of blood as well, showing that the soldier had winged the spy.”

“Tamales and terrapins, but that is thrilling news, Frank!” exclaimed Pudge. “Did you try to follow the trail, and see if the poor fellow was lying around anywhere?”

“It made for the road, and we lost it there,” said Frank. “I reckon it was not a very severe wound, for while the man evidently limped he did not lose much blood. Not wanting to be away from the hangar any longer than we could help, the sergeant and myself came back.”

“One good thing,” remarked Billy, “those chaps will have learned that we are on the job, all right. They’ll be careful how they come sneaking around here again, or try to blow up our plant. What time is it now?”

“Just two o’clock,” announced Pudge, referring to his nickel watch by the light of the lantern which had not as yet been extinguished.

“Between four and five hours more to put in before day comes ‘a-peeping over the hills,’” half sang Billy, as he started to arrange his rude bed again, for in the haste of their turning out, things had been thrown aside rather recklessly.

There was no further alarm that night. Apparently, those who would have given much to have wrecked the hangar with its contents, so as to prevent its being taken over by the French military authorities, feared to again approach the guarded stockade.

Billy, after all, was the first to discover signs of dawn through the window which was secured with the heavy wire mesh. He immediately aroused the others and they proceeded to get the coffee on the stove.

Just when they would receive the signal was uncertain; so that it was considered the part of wisdom to be prepared in advance.

“I wonder where we’ll take the next meal,” Pudge remarked, as they sat there at the table and satisfied their appetites with what had been prepared.

Billy was about to make some sort of grim joke on the possibility of their not ever needing another “feed,” but on second thought he desisted. It was not a subject to be made fun of, he concluded, because the danger of an accident was always in evidence when far up among the clouds.

“We’ll make up a snack to take along with us,” said wise Frank. “It may come in handy, you know.”

“Pumpkins and partridges, but it does take you to think up things, Frank!” cried Pudge, beaming on his comrade, for that proposal was right in his line of weakness.

“There’s someone at the door, Frank!” announced Billy.

The day was coming on, as Frank could see when he partly opened the door. He discovered a stranger standing there, a swarthy looking, slender man, who was apparently a Frenchman, if appearances went for anything.

“Pardon, but have I the pleasure of addressing M’sieu Frank Chester?” he asked.

“That is my name,” replied the boy. “Have you come from Major Nixon?”

“I have a letter here from that gentleman,” said the other. “It is to prove that my identity is correct. For I am to accompany you on this interesting trip, to discover what strong points your seaplane develops. My name, young M’sieu, is Armand Le Grande.”

Frank was thrilled when he heard the name, for he knew that Major Nixon had been wise enough to send one of the most famous of all French aviators to accompany the Sea Eagle on its dangerous mission.