As the “Knobs”--which is the name given to the high hills back of New Albany--receded, the day was still young. It was also overcast and cool. So Ed, who was always studying something, brought his big map up on deck and, spreading it out, lay down on his stomach to study it. He worked over it till dinner time, and in the afternoon he spread it out again. The boys having gathered around him, he said:-- “I say, fellows, we are making a journey that we ought to remember as long as we live. We are going over a small but important part of the greatest river system in the world.” “‘Small but important part,’” said Will, quoting. “Well, I like that.” “What’s your objection,” said Ed Lowry, for the moment borrowing Irv Strong’s playful method,--“what’s your objection to my carefully chosen descriptive adjectives?” “Well, we’re going over pretty nearly the whole of it, aren’t we?” “Not by any manner of means,” responded Ed. “We aren’t going over more than a small fraction of it.” “Why, the Ohio River alone is thirteen hundred miles long,” said Will; “I remember that much of my geography; and most of the Mississippi lies below the mouth of the Ohio, doesn’t it?” “It’s lucky you’ve passed your geography examinations in the high school, Will,” said Ed. “Now come here, all you fellows, and take a look. This map shows the entire system of rivers of which the Mississippi is the mother. It is the greatest river system in the world. There is nothing, in fact, to compare it with but the Amazon and its tributaries, and they have never done anything for mankind, because they lie almost wholly in an unsettled and uncivilized tropical region that has no commerce and no need of any, while the Mississippi and its tributaries have built up an empire. They have in effect _created_ the better part of this vast country of ours that is feeding the world and--” “Oh, come now,” said Irv Strong. “You aren’t writing a composition or an editorial for the Vevay _Reveille_.” This was in allusion to the fact that Ed sometimes published “pieces” in the local newspaper. “Well, no,” said Ed, laughing at his own enthusiasm. “Besides, I’ll come to all that some other time perhaps. At present I want to give Will some new ideas about the bigness of our river system. True, the Ohio is twelve or thirteen hundred miles long, but about half of it lies above Vevay, so we’re covering only six or seven hundred miles of it. From Cairo to New Orleans--the part of the Mississippi we shall traverse--is about one thousand and fifty miles long. So we’re only going to travel over sixteen or seventeen hundred miles of river. Now there are about fifteen or sixteen thousand miles of this river system that steamboats can, and actually do, navigate, and nobody has ever really reckoned the length of the rest--the parts not navigable. We’re going over only about one-tenth of the navigable part--one twenty-fifth part perhaps of the whole.”