Chapter XIX. The Caves of Ice
 

"Keep on firing! Hold 'em back a few minutes and I'll soon turn my electric rifle loose on 'em!" yelled Tom Swift as he sprinted forward. "Keep on shooting, Mr. Damon!"

"Bless my powder-horn! I will!" cried the excited man. "I'll fire all the cartridges there are in the rifle!"

Which, at the rate he was discharging the weapon, would not take a long time. But it had the effect of momentarily checking the advance of the creatures.

Not for long, however. Our friends had barely reached the airship, with Mr. Parker stumbling and slipping on the ice and snow, ere the musk oxen came on again, with loud bellows.

"They're going to charge the ship! They'll ram her!" yelled Ned Newton.

"I think I can stop them!" cried Tom, who had leaped toward his stateroom. He came out a moment later, carrying a peculiar-looking gun, The adventurers had seen it before, but never in operation, as Tom had only put some finishing touches on it since undertaking the voyage to the caves of ice.

"What sort of a weapon is that?" cried Abe, as he helped Mr. Parker on board.

"It's my new electric rifle," answered the young inventor. "I don't know how it will work, as it isn't entirely finished, but I'm going to try it."

Putting it to his shoulder he aimed at the leading musk ox, and pulled a small lever. There was no report, no puff of smoke and no fire, yet the big creature, which had been rushing at the ship, suddenly stopped, swayed for a moment, and then fell over in the snow, kicking in his death agony.

"One down!" yelled Tom. "My rifle works all right, even if it isn't finished!"

He aimed at another ox, and that creature was stopped in its tracks. Mr. Damon had exhausted his cartridges, and had ceased firing, but Abe Abercrombie was ready with his rifle, and opened up on the beasts. Tom killed another with his electric gun, and Abe shot two. This stopped the advance, and only just in time, for the foremost animals were already close to the ship, and had they rushed at the frail hull they might have damaged it beyond repair.

"Here goes for the big one!" cried Tom, and, aiming at the largest ox of the herd, the young inventor pulled the lever. The brute fell over dead, and the rest, terror stricken, turned and fled.

"Hurrah! That's the stuff!" cried Ned Newton, capering about on deck. He had hurried to his stateroom and secured his rifle, and, before the musk oxen were out of sight he had killed one, which gave him great delight.

"Mighty lucky we drove them away," declared Abe. "They are terrible savage at times, an' I reckon we struck one of them times. But say, Tom, what sort of a gun is that you got, anyhow?"

"Oh, it fires electric bullets," explained our hero. "But I haven't time to tell you about it now. Let's get out and skin one of those oxen. The fresh meat will come in good, for we've been living on canned stuff since we left Seattle. We've got time enough before it gets dark."

They hurried to where the shaggy creatures lay in the snow, and soon there was enough fresh meat to last a long time, as it would keep well in the intense cold. Tom put away his electric gun, briefly explaining the system of it to his companions. The time was to come, and that not very far off, when that same electric rifle was to save his life in a remarkable manner, in the wilds of Africa where he went to hunt elephants.

In the cozy cabin that night they sat and talked of the day's adventures. The airship had been slightly lifted up by means of the gas bag, and now rested on a level keel, so it was more comfortable for the gold hunters.

"I did not complete my observations about the great snow slide," remarked Professor Parker, "I trust I will have time to go over the ground again to-morrow."

"We leave early in the morning," objected Tom.

"Besides, I don't believe it would be safe to go over that ground again," put in Mr. Damon.

"Bless my gunpowder! But when I saw those savage creatures rushing at you, I thought it was all up with us. Are you hurt, Parker, my dear fellow? I forgot to ask before."

"Not hurt in the least," answered the scientist. "My heavy and thick fur garments saved me from the beasts' horns, and I fell in some soft snow. I was quite startled for a moment. I thought it might be the beginning of the snow movement."

"It was an ox movement," said Ned, in a low voice to Tom.

Morning saw the travelers again under way, with the Red Cloud now floating high enough to avoid the lofty peaks. The weather was clear but very cold, and Tom, who was in the pilot-house, could see a long distance ahead, and note many towering crags, which, had the airship been flying low enough, would have interfered with her progress.

"We'll have to keep the searchlight going all night, to avoid a collision," he decided.

"Are we anywhere near the place?" asked Mr. Damon.

"We're in th' right region," declared the old miner. "I think we're on th' right track. I recognize a few more landmarks."

"There wouldn't have been any trouble if I hadn't lost the map." complained Tom, bitterly.

"Never mind about that," insisted Abe. "We'll find th' place anyhow. But look ahead there; is that another hail storm headin' this way, Tom?"

The young inventor glanced to where Abe pointed. There was a mist in the air, and, for a time great apprehension was felt, but, in a few minutes there was a violent flurry of snow and they all breathed easier. For, though the flakes were so numerous as to completely shut off the view, there was no danger to the airship from them. Tom steered by the compass.

The storm lasted several hours, and when it was over the adventurers found themselves several miles nearer their destination--at least they hoped they were nearer it, for they were going it blind.

Abe declared they were now in the region of the gold valley. They cruised about for two days, making vain observations by means of powerful telescopes, but they saw no signs of any depression which corresponded with the place whence Abe had seen the gold taken from. At times they passed over Indian villages, and had glimpses of the skin-clad inhabitants rushing out to point to the strange sight of the airship overhead. Tom was beginning to reproach himself again for his carelessness in losing the map, and it did begin to took as if they were making a fruitless search.

Still they all kept up their good spirits, and Mr. Damon concocted some new dishes from the meat of the musk oxen. It was about a week after the fight with the savage creatures when, one day, as Ned was on duty in the pilothouse, he happened to lock down. What he saw caused him to call to Tom.

"What's the matter?" demanded the young inventor, as he hurried forward.

"Look down there," directed Ned. "It looks as if we were sailing over a lot of immense beehives of the old-fashioned kind."

Tom looked. Below were countless, rounded hummocks of snow or ice. Some were very large--as immense as a great shed in which a dirigible balloon could be housed--while others were as small as the ice huts in which the Eskimos live.

"That's rather strange," remarked Tom. "I wonder--"

But he did not complete his sentence, for Abe Abercrombie, who had come to stand beside him, suddenly yelled out:

"The caves of ice! The caves of ice! Now I know where we are! We're close to the valley of gold! There are the caves of ice, and just beyond is th' place we're lookin' for! We've found it at last!"