The young travelers did not have so long to wait as they had feared. That very night, as they sat about their fire on their bed rolls, talking of their many trips together, they heard in the darkness not far away the tremulous note of a screech owl, repeated again a moment later. Jesse stopped talking, turning his head. Rob laughed: "That's Uncle Dick now!" he said, in a low tone; and answered with an owl call just like the one they had heard. They heard a laugh in the dark, and from behind the tent stepped Uncle Dick. "How!" said he. "How!" said each of the boys gravely. Rob made the Indian sign of "sit down"--his fist struck down on the robe that was spread by the little fire. Their companion sat down, not saying a word. Pretty soon he began to talk in "sign talk," the boys all watching closely. _"Me. Gone. Two sleeps. I come here, now, me. Sun comes up. We go. We. Cross water. Horse--four. Ah! Two----"_ Uncle Dick broke out laughing. John shook his fingers, loosely, to say, "What's that?" "That's what I don't know!" Uncle Dick said, laughing again. "I don't know what the sign is for 'mule.' It isn't elk, or deer, or wolf, or buffalo. Oh, of course, split fingers over another finger--that means 'Ride horse.' But that does not mean 'mule'! And if I put on ears, how'd you know I didn't mean 'deer with-big-ears,' or 'mule deer,' and not 'mule'? The Indians had mule deer, but they didn't have mules!" "Yes, they did!" said Jesse. "The _Journal_ says they bought one mule of the Shoshonis, away west of here!" "Does it? I'd forgotten. Well, I'd like to know where those people got that mule out here, in 1805! I'd have been no more surprised to see a mastodon really walking around out here. Of course, you know that President Jefferson wrote Lewis not to be surprised if he did see the mastodon still living in this unknown country. You see, all of them knew about the mastodon bones found in the Big Lick, Kentucky. They didn't know a thing about this new world we'd just bought of Napoleon, mastodons, mules, and all. "Well, anyhow, Billy Williams has his camp five or six miles from here, across, and he has four saddle broncs and two perfectly good mules for the packs--one plumb black and one plumb white--both ex-army mules and I suppose fifty years or so old. I think old Sleepy, the white one, is the wisest animal I ever saw on four legs--I've been out with Sleepy before, and with Billy, too. Good outfit, boys--small, no frills, all we need and nothing we don't. "I've left our outboard motors here in town with a friend. Most wish we hadn't brought them around. But we'll see how much time we have when we get done projecting around at the head of the river. "I can promise you some knotty problems up in there. To me, what's ahead of us in the next two weeks was the most exciting part of the whole Lewis and Clark trip across." "But, Uncle Dick, you promised us some sport--fishing, I mean--trout and grayling."