Onward sped the Red Cloud. For a moment after the accident to Andy's ship, Tom had slowed up his craft, but he soon went on again, after he had satisfied himself that his enemies were in no danger.

"Don't you think--that is to say--I know they can't expect anything from us," spoke Mr. Damon, "but for humanity's sake, hadn't we better stop and help them, Tom?"

"I hardly think so," replied the young inventor. "In the first place they would hardly thank us for doing so, and, in the second, I don't believe they need help. They are almost safely down now."

"I don't just mean that," went on the odd man. "But they may starve to death. This is a very desolate country over which we are sailing."

"They must have a supply of food in their ship," declared Tom, "and they have brought their plight on themselves."

"They're in no great danger," put in Abe.

"There are plenty of natives around here, an' if the Fogers need food or aid they can git it by payin' for it. Why, for the sake of th' parts of their damaged airship, th' Eskimos would take th' whole party back t' Sitka and feed 'em well on th' trip. Oh, they're all right."

"Very well, if you say so," assented Mr. Damon. He looked back to watch the Anthony slowly settling to earth. It came gently down, proving that Tom knew whereof he spoke, when he had said they could vol-plane down. Before the Red Cloud was out of sight Tom and his companions saw Andy and his father leave their wrecked craft and venture out on the snow-covered ground. The Fogers gazed enviously after the airship of our hero as they saw him still forging toward the goal.

"I guess Andy's stolen map won't be of much use to him," mused Tom. "Now we can put on all the speed we like, "and with that he shifted the gears and levers until the airship was making exceedingly good time toward the valley of gold.

The remainder of that day saw our adventurers pursuing their way eagerly. At times they were flying high, and again, when Abe suggested that they go down to observe the character of the country over which they were passing, they skimmed along, just above the big mountains, which seemed almost like icebergs, so covered were they with frost and snow.

They were indeed in a wild and desolate country. Below them stretched a seemingly endless waste of snow and ice--great forests interspersed with treeless patches, while now and then they sailed over a frozen lake.

Once in a while they had glimpses of bands of Indians, dressed in furs, hunting. At such times the natives would look up, on hearing the noise made by the motor of the airship, and catching a glimpse of what must have seemed to them like some supernatural object, they would fall down prostrate in amazement and fear.

"Airships are pretty much of a novelty up here," remarked Abe with a grim smile.

The weather was new very cold, and the gold-seekers had to get out their heavy fur garments, of which they had brought along a goodly supply. True, it was warm in the cabin of the airship, but at times, they wanted to venture out on the deck to get fresh air, or to make some adjustments to the wing planes, and, on such occasions the keen, frosty air, as it was driven past them by the motion of the craft, made even the thickest garments seem none too warm. Then, too, it was colder at the elevation at which they flew than down on the ground.

Another day found them in a still wilder and more desolate part of Alaska. There were scarcely any signs of habitation now, and the snow and ice seemed so thick that even a long summer of sunshine could hardly have melted it. The hours of daylight, too, were growing less and less the farther north they went.

"Do you think you can pilot us right to the Snow Mountains, Abe?" asked Tom, on the third day after the accident to Andy's airship. "Let's get out the map, and have another look at it. We must be getting near the place now. We'll look at the map."

The young inventor went to his stateroom where he kept the important document in a small desk, and the others heard him rummaging around. He muttered impatiently, and Ned heard his chum say: "I thought sure I put it in here." Then ensued a further search, and presently Tom came out, his face wearing rather a puzzled and worried look, and he asked: "Say, Abe, I didn't give that map back to you; did I?"

"Nope," answered the miner. "I ain't seen it since just before th' hail storm. We was lookin' at it then."

"That's when I remember it," went on Tom, "and I thought I put it in my desk. I didn't, by any possible chance give it to you; did I, Ned?"

"Me? No, I haven't seen it."

"That's funny," went on Tom. "I'll look once more. Maybe it got under some papers."

They heard him rummaging again in his desk.

"Bless my bank-book!" cried Mr. Damon. "I hope nothing has happened to that map. We can't find the valley of gold without it."

Tom came back again.

"I can't find it." he said, hopelessly.

Then ensued a frantic search. Every possible place in the airship was looked into, but the precious map did not turn up.

"Perhaps the Fogers took it," suggested Mr. Parker, who had helped in the hunt, in a dreamy sort of fashion.

"That's not possible," said Tom. "They haven't been near enough to us since I saw the map last. No, the last time I had it was just before the hail storm, and, in the excitement of repairing the ship, I have mislaid it."

"Maybe it's back there in the big cave," suggested Ned.

"It's possible," admitted the young inventor. "Pshaw! It's very careless of me!"

"If you think it's in the cave, we'd better go back there and have a hunt for it," suggested Mr. Damon. "Otherwise we are on a wild-goose chase."

"Don't go back!" exclaimed old Abe. "I think we can find th' valley of gold without th' map, now that we have come this far. I sort of remember th' marks on that parchment, an' we are in the right neighborhood now, for I kin see some of th' landmarks my partner and I saw. I say, let's keep on! We can cruise around a bit until we strike th' right place. That won't take us so long as it would to go back to the cave. Besides, if we go back, the Fogers may get ahead of us!"

"With their broken airship?" asked Ned

"Can't they repair it?" demanded Abe.

"Hardly--up in this wild country," was Tom's opinion. "But perhaps it will be just as well to keep on. I have a hazy remembrance of the distances and directions on the map, and, though it will take longer to hunt out the valley this way, I think we can do it. I can't forgive myself for my carelessness! I should have kept a copy of the map, or given one of you folks one."

But they would not hear of him blaming himself, and said it might have happened to any one. It was decided that the map must be lost in the big cave, and if it was there it was not likely to be found by their enemies.

"We'll jest have t' prospect about a bit," declared Abe, "only we'll do it in th' air instead of on th' ground."

It was dusk when the fruitless search for the map was over, and they sat in the cabin discussing matters. The lights had not yet been switched on, and the Red Cloud was skimming along under the influence of the automatic rudders and the propellers.

"Well, suppose we have supper," proposed Mr. Damon, who seemed to think eating a remedy for many ills, mental and bodily. "Bless my desert-spoon, but I'm hungry!"

He started toward the galley, while Tom went forward to the pilothouse. Hardly had he reached it than there came a terrific crash, and the airship seemed tossed back by some giant hand. Every one was thrown off his feet, and the lights which had been turned on suddenly went out.

"What's the matter?" cried Ned.

"Have we hit anything?" demanded Mr. Damon.

"Hit anything! I should say we had!" yelled Tom. "We've knocked a piece off a big mountain of ice!"

As he spoke the airship began slowly settling toward the earth, for her machinery had been stopped by the terrific impact.