Half a day's riding brought them to a wild part of the country. The trail was a narrow one. Now it led along a high range of foothills, skirting some deep ravine. Again it was down in a valley, along the course of some mountain stream that was now almost dry.

The bracing atmosphere, though it was so rarefied that the boys, at first, found a little difficulty in breathing, made objects seem strangely near. Several times Jack and his companions saw a distant landmark, and wondered why they were so long in reaching it. Mr. Hardy laughed at their astonishment as he explained the reason for the seeming nearness.

They had dinner on the side of a mountain which they had begun to ascend shortly before noon. Mr. Hardy proved himself an old campaigner. He had a fire made, and bacon frying before the boys had the stiffness from their legs, caused by their ride. Then, with bread and coffee, they made a better meal than they had partaken of in many a hotel.

That night they slept in a lonely mountain cabin, the owner of which Mr. Hardy knew. They pressed on the next morning, their pace being slow because Nat found he could not ride as well as he had hoped.

"Galloping gooseberries!" he exclaimed. "I feel as if all my bones were loose. You didn't see any of 'em scattered back along the trail, did you, Jack?"

"You'll get over it," said Mr. Hardy. "Got to learn to ride if you're going on a ranch. No one walks there."

They had to sleep in the open the next night, but Mr. Hardy built a big fire, and, well wrapped in their blankets, the boys were not uncomfortable, even though it was cold on the mountain from the time the sun went down.

It was cold, too, the next morning, as they crawled from their warm coverings, but when their guide had thrown a lot of wood on the glowing embers, causing them to spring into a fine blaze, the boys got up and helped prepare breakfast.

"We're almost there," said Mr. Hardy, as they mounted their horses to resume their trip.

They rode until shortly before noon, when Mr. Hardy suddenly pulled his horse up and said: