Such undoubtedly would have been the action of the tramps, had not it changed so abruptly and inexplicably that the astounded doctor ceased paddling and stared without speaking a word.
Since our friends sat with their faces toward the backs of Biggs and Hutt, they saw their every movement no matter how slight. Hutt was idle, with a grimy hand resting on either gunwale of the canoe. Now and then he glanced back and when he saw the pursuers steadily falling behind, had the impudence to reach out one hand and beckon them to move faster. The other, knowing he could not be overtaken, showed little interest in those who were striving to come up with him. Something far in advance seemed to hold his attention.
Such was the situation, and the forward boat was within a furlong of the western shore when Biggs suddenly held his paddle suspended as if he had caught sight of some object that startled him. The next moment he flung aside the implement, uttered a cry of terror and dived overboard. Hutt was not five seconds behind him. Both stayed so long under water that our friends suspected they were drowned, but the frowsy heads, one without a hat, bobbed up at some distance from the boat, and they were seen swimming furiously toward the northern bank, which was not far off.
They had not taken a dozen strokes when they dived again and went as far under the surface as before. Thus diving, swimming and working desperately, they quickly reached land, scrambled out, plunged in among the trees and vanished as if Death himself were nipping at their heels. Never was greater panic shown.
Doctor Spellman sat mute and motionless until the tramps had disappeared. Then he turned his head:
“What do you make of that, Mike?”
The occasion was one of the rare ones when the Irish youth had nothing to say. He sighed and shook his head; he couldn’t do justice to the theme.
“Something scared both of them out of their wits. It couldn’t have been on the shore ahead, for that’s too far off, nor on their right, for they tried with might and main to reach land there.”
“Could it have been at the rear?” ventured Mike.
“That is toward us. We couldn’t have caused them such alarm.”