when it's gone," he said.

"I say, Major," exclaimed Bruce, "I've been thinking of those white reindeer. Don't you suppose that solves the problem of Peary's white reindeer?"

There was a peculiar twinkle in the Major's eye, as he asked: "How do you make that out?"

"Well, there had been reindeer in Alaska for twenty-five years when Peary discovered his on the eastern coast of our continent. There are many white ones among the domestic herds, and they are constantly wandering away, or being driven away, by packs of wolves. If they wandered this far, might they not easily have gone on to the other side of the continent?"

"Possibly. Possibly," The twinkle in the Major's eye grew brighter, but he said no more. Presently he rose and stepped outside.

"Say!" exclaimed Barney, "I feel like turning right around and going back."

Bruce knew that he was thinking of La Vaune's money. "But we can't," he sighed. "It's not our plane nor our expedition. We're bound by agreement to go on. Besides, there's no real need of going back. La Vaune's all right for the winter. I arranged for her at my old college at Brandon; she will attend the academy and help in the dining-room."

"Well, then," said Barney, "I guess it's us for union-alls and at those engines."

They were soon at their task. But, as Bruce worked that day, he thought often of the mysterious twinkle he had seen in the Major's gray eyes, as he spoke of the white reindeer. Who was this Major, anyway? And where were they going? The Major alone could tell, and apparently he had no intention of doing so.

CHAPTER III

IN THE MIDST OF THE PACK

"I think," said the Major, on the third morning after their strange landing, "that we would make a great mistake to set out again at this time. We are not likely to have the luck of our last landing a second time. Then too, if we remain here until the lakes and rivers are frozen over, we can find a safe landing place every few miles.

"And now," the Major continued, stirring the fire thoughtfully, "now I think it would be right that I tell you something of the purpose of this journey."

The boys leaned forward, eager for the story.

"Even now," he said slowly, "I do not feel like confiding to you what I may consider my great secret plans—plans for which this journey is but a trial-trip into the frozen North. That may follow in good time. But, as for this present journey, you are perhaps aware that an illegal wireless station has been operating somewhere in these woods and hills?"

"Yes—yes; we saw the offer of reward!" exclaimed Barney.

"The reward is a small matter," smiled the Major. "Should we be so fortunate as to capture the culprit, or be able to certify to his death, I will gladly turn over the reward to you boys."

"Thanks," said Barney, who already had his share of the prize in his purse.

"First I shall tell you the purpose of that wireless and why it is so important to locate it," the Major went on. "It is one of the links in a chain around the world—a chain that threatens to bind civilization to a burning stake of sedition, anarchy and bloodshed. The operator is an anarchist, or, at least, belongs to an allied organization, and these, one and all, have for their purpose the destruction of the present order of things. Now, there is not one of us but believes that there are many evils possible—yes, and put in operation under the present order, but we do not believe that matters are going to be bettered by a world-revolution. We believe that in time justice will come very much nearer being done under the old system; therefore, we are fighting to maintain it. That is why I volunteered to attempt to hunt out and if possible destroy this powerful wireless station, which is relaying revolutionary messages direct from Russia to all important points in North America. My long experience in the North seemed to fit me for that task; and it is a task that I am determined to accomplish.

"It is my theory that this wireless is located on the shores of Great Bear Lake. In fact, I believe it is run by an independent trader operating at the east end of that lake, on Conjurer's Bay. A year ago he brought in a small electric plant, to light his trading post, he said. Now this plant is capable of producing an almost unlimited amount of electrical power, provided only time is given. Batteries of great power might easily be produced on the spot. Chemicals for producing acids are found in abundance; so also are copper and zinc for the plate. All he would have to do then would be to make wooden boxes for the chemicals, erect his wires—he could string them from spruce poles—and the thing is done. It was impossible to reach the station by water after I had guessed its location, and there was of course the possibility that I was wrong, that it was nearer civilization. In that case I might be able to locate it, providing I made the trip by plane."

"That explains why we circled three times during our first day's flight?
You were looking—"

"For the wireless tower," smiled the Major.

"And now," he went on, "I think we will just rest easy on our wings for a few weeks. You will get the engines in shape; take a few trial flights, if you wish, but be careful to conserve gasoline. We must have enough to carry us to Great Bear Lake. There we will find a sufficient supply to carry us on any other journey we may decide on. The trader uses gasoline to run his electric plant and will have a supply. It will not be of very high test, but with two engines I think we will make it answer our purpose. If we find that my theory regarding the location of the tower is not correct, we will buy a supply from him, and if it is correct—" He did not finish, but smiled and poked the fire again.

"Take it all in all," said Barney to Bruce some time later, "I think our trip promises to be dangerous enough to satisfy even a bloodthirsty young savage from the Canadian army."

"Or a young Cherokee from the wilds of Boston Commons," laughed Bruce, heaving a wrench in the general direction of his companion.

But, though they went about their work in a playful mood, they did it with great care. After they had taken the two little Timmies for several rides, they declared the airship quite ready for further voyaging. "And as for gasoline," said Bruce, "we still have two hundred and forty gallons in the tank which will give us a-plenty for the trip, and several hours to spare; but coming back—that's another matter."

Barney realized that this was, indeed, another matter, and, though he shared the Major's hope of securing a supply at the trading station, his face grew grave at thought of being stranded more than a thousand miles from civilization at the beginning of winter, and with only a few days' supply of provisions. What if this trading station was one of those myths that float down from the North? Or, what if it had been abandoned?

Barney shook himself free from these thoughts, and seizing his mandolin, went to join Bruce and Timmie on saxophone and rudely-devised Indian kettledrums in a wild-woods symphony, while the children danced wild steps the boys had never seen.

* * * * *

"Well, we're off!" Barney said this, as he buckled on his harness and touched the starting lever. The wheels of the starting gear bumped over the thin-crusted snow and jolted through Timmie's wheat stubble, then the great bird began to rise.

Winter had set in. Now they glided over dark forests of spruce, and now swept