Noon came and went, with the same steady progress being maintained hour after hour. Tom relieved Beverly at the pilot's berth, and the latter succeeded in getting some much needed rest. Still, none of them could sleep comfortably, which was hardly to be wondered at considering their strange surroundings.

"My first nap when flying, for a fact!" admitted Colin, after he had awakened, and managed to stretch his stiffened limbs.

"Tough work trying to get a few winks of sleep when one is quivering all over with excitement," Jack remarked.

They were no longer maintaining such a high course, having descended until the heaving sea lay not more than a thousand feet below. Nothing was in sight in any direction, which was one reason for Tom's dropping down as he did.

"A lot of water," Jack commented, for they had started to try out the wonderful little wireless telephone, to find that it really worked splendidly. "Guess after the flood Noah must have thought that way too. But shucks! we haven't got even a dove to send out."

"We happen to have something better," Tom told him, "which is the power to shoot our boat through space at the rate of a mile a minute. No ark business about this craft."

"Well, is there any objection to breaking our fast again?" the other inquired, changing the subject.

Beverly seemed to think not, for he proceeded to get out the hamper in which much of their prepared food was contained.

"I laid in double the quantity I expected we'd devour," he told them, "and then added something to that for good measure. No telling what may crop up; and if we happen to be cast on a desert island a healthy lot of grub might come in handy."

"It does right now, when we are far from any island, unless that's one up there in that dark cloud floating above us," and Jack stretched out to receive his portion of the lunch as parceled out by Colin.

"One thing that made me drop to a lower level," explained Tom, "was the fact of its being so cold up there among the clouds. Already I feel better for the change."

"How about it if we should sight a steamer?" asked Jack. "They'd report meeting a plane flying west here in midocean, which would stir up no end of comment in the papers, and might lead to our being found out."

"We depend on you to keep the glasses in use, and report anything in sight ahead," laughed Tom; for the clatter of the motors did not seem to bother them in the least when using the wireless telephone. "And when you sing out 'smoke down low on the horizon to the west!' it's going to be an easy job for us to climb up above the clouds in a hurry."

So it was settled, and they ate their lunch in comfort.

Up to that time not the slightest thing had arisen to give them concern with regard to the working of the engines. These aroused the admiration of the three voyagers by their remarkable performance. Tom declared their equal had never been installed in any plane that was ever built, and Lieutenant Beverly's eyes glowed with satisfaction to hear his pet praised so cordially by one whose good opinion he valued as highly as he did Tom Raymond's.

After Jack had taken his turn at piloting the machine, he amused himself "between naps" by watching the surface of the sea through the binoculars.

"No telling but what I may glimpse a submarine creeping along under the surface," he told the others jokingly. "Then wouldn't we wish we'd brought along a few bombs—the kind they dropped on that Hun bridge the night we went with the raiders. Right now I could almost imagine that shark's dorsal-fin was a periscope belonging to an undersea boat."

Other things came along to cause momentary interest, among them rolling porpoises that rose in sight, and then vanished under the waves, though from their height the boys could easily follow their movements.

Jack was getting a good deal of enjoyment out of the situation, and Tom was glad to notice this fact. He had feared his chum's nerves might give way under the long-continued strain; but apparently Jack had returned to his ordinary condition.

All of them rather dreaded the coming of night. Flying in midocean while daylight lasted was serious enough, but with darkness around for many hours, the situation must awaken new anxieties.

But their hearts were still apparently undaunted. The success that had rewarded their bold starting out gave abundant promise of still better things ahead. Tom resolutely refused to allow himself to have any fear. What if two thousand miles still lay between them and the goal of their hopes? Was not the miracle-worker of a monster plane doing remarkably fine work, and should they not continue to believe the end justified the means?

So they watched the sun dropping lower and lower in the western sky without any one voicing the thought that must have been in each mind. The same inscrutable Providence that had watched over them by day would still guard them when the light was gone. Under the stars, seeming now so much nearer and brighter than when ashore, they went on and on, until back in the east another day dawned, the great day of hope for them!

Jack had taken to looking eagerly ahead once more.

"What do you think you see?" Beverly asked him, for Tom again served as pilot at the steering gear.

"Why, I'm all mixed up about it," came the slow reply. "It certainly isn't a steamer, and again it just can't be land!"

"Well, hardly," Beverly answered. "To tell the honest truth I don't believe there's a foot of land closer to us than the Bermudas, which must lie off in that direction," pointing further toward the southwest.

"When the sun glints on it I'm fairly dazzled," Jack continued, "just as if some one had used a piece of broken looking-glass to shoot the rays into my eyes. And then there's a sort of queer mist hanging about that thing in the bargain, so that sometimes it's almost blotted out. What under the sun can it be?"

"I think I can give a guess," Tom called back. "How would an iceberg fill the bill, Colin?"

"Just the thing, I'd say," the lieutenant answered, "only who ever heard of an iceberg floating down in mid-Atlantic at this season of the year? Such a thing would be uncommon, to say the least."

"But not impossible?" ventured Tom, to which the other agreed.

"Take a look, and tell us, Colin," urged Jack, offering the glasses.

A minute afterwards they were handed bade again.

"Just what it is, Tom, after all," reported Beverly. "A pretty tall berg it seems to be, with an extensive ice-floe around it as level in spots as a floor. I thought I saw something move on it that might be a Polar bear, caught when the berg broke away from its Arctic glacier. We will pass directly over, and may be able to feel the chill."

"It was the Titanic, wasn't it, that bumped into an iceberg, and went down with such a frightful loss of life?" remarked Jack.

"No other," replied Tom. "But we'll try to make sure nothing like that happens to our frail craft. Try to guess what would happen to that monster berg if we hit head on?"

"Hardly a crack!" Jack retorted. "But I'm more interested in wondering what would become of us. Guess we'd better keep a good thousand feet up, and not bother trying to pry into the ice-floe's secrets."

"I'm not dreaming of dropping a foot lower just at present," Tom said decisively; and not one of them dreamed how soon that decision would have to be reversed, since all still looked fair about them, with no storm in sight and the wonderful motors kept up their regular pulsations as if capable of going on forever.

Yet strange vicissitudes and changes are the portion of those who follow the sea; which may also be applied to other voyagers of space, the sailors of the air. One minute all seems fair, with the sun shining; another, and a white squall is dashing down upon the ship, to catch the crew unawares and perhaps smother them with its mighty foam-crested billows.

It was not half an hour later when something happened that was calculated to chill the hearts of those bold navigators, such as even close contact to the ice-floe and berg could never bring about.

At the time they had reached a point almost above the field of ice from the Arctic regions, and Jack was scrutinizing its full extent, commenting the while on many peculiar features that attracted his attention.

"It's a Polar bear, all right, fellows," he announced, "and believe me he's some size in the bargain. If I had a rifle along I wouldn't mind dropping down there and rustling him. But what ails you, Tom? You seem bothered about something. Gee! you're as white as a ghost!"

Lieutenant Beverly leaned forward and clutched the pilot's arm.

"Anything gone wrong with the motors, Tom?" he demanded hoarsely.

"I've just made a terrible discovery," replied Tom, trying to control himself. "The worst has happened, and I'm afraid we're in for a bad time!"