“The tide.”
“Why, yes—so it will; and keep us back, too, when it’s running out.”
“Not if we time our stops the way we ought to.”
“If you fellows wish, I can figure out just how it changes. I think there’s about an hour’s difference every day.”
“That’s knowledge for you,” laughed Jack. “Don’t wonder you wear glasses, and forget to smile at times, old chap.”
“It’s one of the terrible effects of deep thought,” grinned Joe. “But still, I should say so much brain work isn’t necessary just now. We’ll drop in a string—if it floats down—well—it follows——”
“The tide,” said Jack.
“Aristotle would have envied such reasoning as that,” laughed Dave Brandon. “What a relief to know that the weighty problem is settled.”
Becoming emboldened by the ease with which he handled the “Gray Gull,” Jack decided to venture further out into the stream.
For half an hour they had kept their course, when Fred Winter adjusted his glasses, and, looking straight ahead, exclaimed: