Tom, seeing that Sam was getting better at last, began to hope for his complete recovery, and the hope made him buoyant of spirit again. Judie, too, who watched and weighed every symptom in Sam's case, discovered to her delight that he was decidedly better, and the discovery made her as happy as a healthy girl well can be. Poor Joe seemed to be the only miserable one in the party. He said almost nothing, answering questions with a simple "yes" or "no," and sitting moodily in his corner, when he stayed inside the "drift cavern"—which was Sam's name for the new abode—at all. He spent most of his time, however, on top of the pile, where he watched the water and the clouds. The rain had ceased, but the river, which was now creeping over the broad bank, continued to rise.
"What is the matter with Joe?" asked Sam after the boy had gone out for the twentieth time.
"I think he's afraid we're all going to be drowned," said Tom.
"Drowned? How?"
"Well, he says wood will float, and so he thinks when the water comes up under the drift-pile, it will all float away."
"What nonsense!" exclaimed Sam. "Why didn't you tell him better, Tom?"
"I did; but he sticks to it, and—"
"Well, couldn't you explain it so that he would understand it and not have to trust to your judgment for it?"
"No, I couldn't. The fact is, I don't quite understand it myself. There isn't a stick in this whole pile that won't float, and I don't quite understand why the pile won't. But I don't doubt you're right about it, Sam. You always are right whether I understand how things are or not."
"Let me explain it to you, then. Do you know why some things float and others don't?"