"And you can't beat Dave riding," broke in Roger. "When he was at Star Ranch he busted the wildest bronco you ever saw."

"Is that so! Well, I don't like no wild broncos. I like a good, steady hoss, one as can climb the mountain trails and is sure-footed on the edge o' a cliff. That's the kind we'll git," concluded Tom Dillon.

The remainder of the day proved a busy one. The boys went out with the old miner to secure the horses and such an outfit as he deemed necessary. Then they spent part of the evening in writing letters to the folks in Yellowstone Park and at home. Only one letter came in for them—one from Senator Morr to his son—and this made Roger look very sober.

"No bad news, I hope," said Dave, kindly.

"It's about dad's private affairs," was the reply. "Things have taken something of a turn for the worse financially." Roger gave a sigh. "Oh, I do hope we can locate that lost mine!"

"We all hope that!" said Dave.

"Indeed, we do!" cried Phil. "We've just got to do it," he added, enthusiastically.

Now that he had made up his mind to undertake the expedition, old Tom Dillon brightened up wonderfully, and to the boys he appeared ten years younger than when they had first met him. He was a fatherly kind of a man, and the more they saw of him the better they liked him. He selected the outfit with care, securing five good horses—one for each of them and an extra animal for the camp stuff, and other things they were to take along.

In a place like Butte, where Tom Dillon was so well known, it soon became noised around that he was going on a prospecting tour. Some asked him where he was going, but he merely replied that he was going along with his young friends to show them the mining districts.

"It won't do to let 'em know we are going to look for a mine," he explained, in private. "If we did that, we'd have a crowd at our heels in no time."