My uncle scratched his chin and frowned as he always did when perplexed, and after some thought exclaimed, "Well, I can't let the three of you go! The men down there in the timber are about as timid a set of sheep as ever was. No, Abbott, you'll have to help me here, and the boys must do the best they can."

Pitamakan ran for the horses. I did not ask whether I were to ride Is-spai-u; I just brought him in and put the saddle on him. Pitamakan saddled my runner, for, as you know, his fast horse had had his shoulder gashed by a bullet. My uncle handed me the letter and told us to be very cautious, but to get it aboard the boat at any cost. Tsistsaki came running out and handed us some sandwiches, and we were off.

The Upper Missouri Valley is the worst country in all the West for the rider. It is fine enough going in the wooded or grassy bottoms of varying lengths, but between the bottoms are steep slopes and ridges that break abruptly off into the winding river, and that are so seamed with coulees, many of them with quicksand beds, that they are well-nigh impassable.

I did not intend that we should follow the valley until obliged to do so. On leaving camp we rode on the plain and followed it from breakhead to breakhead. Occasionally we got a glimpse of the valley far below and of the smoke of the steamboat puffing its way up the river. We were soon in the lead of it, for, while we were making seven or eight miles an hour on a straight course, it was going no faster than that on a course as crooked as the body of a writhing snake. From the time we topped the rise above camp we were continually pushing into great herds of buffaloes and antelopes.

On and on we rode until the lowering sun warned us that we must keep close track of the progress of the steamboat. We turned down a little way into the breaks, looking for a well-worn game trail to follow, and soon found one. I never went along one of those bad-land trails without wondering how far back in the remote past it had been broken by a band of thirsty buffaloes heading down from the plains to water. Since that time how many, many thousands of them had traveled it!

When part way down the long incline, and still all of two miles from the river, we came to a sharp turn in the ridge, and from it saw the smoke of the steamboat, not, as we had expected, somewhere down the river, but all of three or four miles above the point where we should enter the bottom.

The sun had set, and the night was already stealing down into the valley; the boat would soon be tied up. There was not a pilot on the river that would venture to guide a steamboat up or down it even in the light of a full moon, and this night there would be no moon until near morning.

"Almost-brother, we have some hard traveling to do!" I said.

"We each have good legs. When our horses fail us, we will use them," Pitamakan answered.

The bottom that we were heading into proved to be all of a mile long, and we traversed it and went over a rather easy point into the next bottom before real night set in. We had starlight then, just enough light to enable us to see in a rather uncertain way forty or fifty feet ahead of our horses. Midway up the bottom we came to the first of our troubles, a cut coulee that ran across it from the bad lands to the river. We turned up along it almost to the slope of the valley before Pitamakan, on foot and leading his horse, found a game trail that crossed it. Presently we arrived at the point at the head of the bottom, and could find no trail leading up it, in itself a bad sign. We both dismounted and began the ascent. Our horses' feet sank deep into the sun-baked, surface-glazed volcanic ash with a ripping, crunching sound as if they were breaking through snow crust. Almost before we knew it we found ourselves on a steep slope with a cut bluff above us and the murmuring river below us. Our horses began to slip.