“Now as all these great rivers of ours, the very greatest in the world, by the way, are in law non-navigable, it follows that the men who own their banks own the rivers also, the man on each side owning to the middle thread of water. Naturally, these men could step in and say that nobody should run a boat through their part of the river without paying whatever toll they might choose to charge. Under such a system it would be impossible to use the rivers at all. It would cost nobody knows how many thousands of dollars in tolls to run a boat, say from Cincinnati to New Orleans.” “Well, why don’t it, then?” asked Will Moreraud. “Why can’t every farmer whose land we pass come out and make us pay for using his part of the river?” “For the same reason,” said Ed, “that the farmer can’t come out and make you pay toll for passing over a public road which happens to cross his land.” “How do you mean? I don’t understand,” said Irv. “Well, the only reason the farmer can’t make you pay toll for crossing his land on a public road is, that the road is made by law a public highway, open to everybody’s use, and it is a criminal offence for anybody to obstruct it, either by setting up a toll-gate, or building a fence, or felling trees across it, or in any other way whatever. And that’s the only reason a man who owns land along these rivers can’t charge toll for their use or put any sort of obstruction in them without getting himself into trouble with the law for his pains.” “How’s that?” asked one of the boys. “This river isn’t a public road.” “That is precisely what it is,” said Ed. “Realizing the difficulty created by the fact that this great river system is not legally navigable while its actual navigation is a common necessity, Congress early passed a law making the Mississippi River and all its tributaries ‘public highways for purposes of commerce.’ That’s why nobody can prevent you from running boats on them, or charge you for the privilege.” The boys were deeply interested in the explanation, which was new to them, and so they sat silent for a while, thinking it over, as people are apt to do when they have heard something new that interests them. Presently Phil said:-- “That’s all very clear and I understand it, but I don’t quite see what it has to do with where we land at Louisville.” “Well,” said Ed, “I can explain that. As the river is a public highway for purposes of commerce, nobody can charge you for any legitimate use of it, or its shores below high-water mark, such use, for example, as landing in front of his property, a thing which may be absolutely necessary to navigation. But if a man or a city chooses to spend money in making your landing easy and convenient, say by building a levee or wharf, putting in posts for you to make your boat fast by, or anything of the kind, that man or city has a right to charge you, not for landing, but for the use of the improvements and conveniences.”