“Yes. This later proved one of the great strategic points of the West. As you know, this was the head of steamboat navigation, and the outfitting point for the bull trains that supplied all the country west and south and north of us. No old post is more famous. But that is not all.
“I have reference now, really, not to Fort Benton, but to the mouth of the Marias River, below here. Now, see how nearly, even to-day, the Marias resembles the Missouri River. Suppose you were captain, Jess, and you had no map and nothing to go by, and you came to these two rivers and didn’t have any idea on earth which was the one coming closest to the Columbia, and had no idea where either of them headed—now, what would you do?”
“Huh!” answered Jesse, with no hesitation at all. “I know what I’d have done.”
“Yes? What, then?”
“Why, I’d have asked that Indian girl, Sacágawea, that’s what I’d have done. She knew all this country, you say.”
“By Jove! Not a bit bad, Jess, come to think of it. But look at your Journal. You’ll find that at precisely the first time they needed to ask her something they could not! The girl was very sick, from here to above the Great Falls. They thought she was going to die, and it’s a wonder she didn’t, when you read what all they gave her by way of medicines. She was out of her head part of the time. They never asked her a thing on the choice of these rivers!
“Well now, what did they do? They spent more than a week deciding, and it was time well spent. They sent out small parties up each fork a little way, and the men all thought the Marias, or right-hand fork, was the true Missouri. Then Clark was sent up the south fork, which was clearer than the other. He went thirty-five miles. If he had gone twenty miles farther, he’d have been at the Great Falls; and the Minnetaree Indians had told of those falls, and of an eagle’s nest there, though they said nothing about the river to the north. Chaboneau had never been here. His wife was nearly dead. No one could help.
“Lewis took a few men and went up the Marias for about sixty miles. They came back down the Marias, and decided on the left-hand fork, against the judgment of every man but Clark.
“His reasoning is good. The men all pointed out that the right-hand fork was roily, boiling, and rolling, exactly like the Missouri up which they had come, whereas the other fork was clear. But Lewis said that this showed that the Marias ran through plains country and did not lead close to the Rockies, from which the water would run clearer; and they did not want to skirt the mountains northerly, but to cross them, going west.
“Lewis had an old English map, made by a man named Arrowsmith, based on reports of a Hudson’s Bay trader named Fidler, who had gone a little south of the Saskatchewan and made some observations. Now look at your Journal, and see what Lewis thought of Mr. Fidler.