As she would have faced about to go on, a faint muffled sound came to her ears; the ground trembled very slightly; a movement of the lake’s surface caught her glance. A moment before, the tiny waves, glistening prisms under the sunlight, had made a scene of quiet beauty. Now, in the twinkling of an eye, there had come a change--a change curious, inexplicable, sinister. Out there in the lake, only a little way from the shore, the water, which had been so placid when they skimmed over it hardly a minute before, was now writhing in a horrible convulsion. Yet, no unwarned tempest racked the lake. The warm air was floating as languidly as hitherto. Nothing had been hurled into the water. There had been no crash of fallen meteor. Naught showed as the cause of this amazing contrast. Nevertheless, under her eyes, the erstwhile tranquil bosom of the lake heaved in rage. Fifty yards from the shore, the water raced, lashing itself in wrath about the sunken center of its vortex. Margaret, thrilled, astounded, terrified, caught May by the arm, pulled her about.
“See! See!” she cried, wildly. “What is it? What can it mean?”
May, too, was stupefied by the spectacle. She stared at it in wordless confusion. She could make no guess as to the cause of this extraordinary event, nor tried to. She merely watched the mad carouse of the flood, and stood aghast. A great fear of this uncanny thing fell on the two girls, so that they clung together for protection, shuddering, their faces pallid.
It seemed to the watchers as if that mysterious turmoil in the waters of the lake continued for hours, though, as Billy Walker might have explained to them, it was doubtless no more than a matter of minutes. The commotion spread over a broad area, but the girls had eyes only for the central place of the movement, the maelstrom near the shore, where the waters whirled in funnel shape, with the swaying hollow pointing the downward rush. An engineer would have known at first glance the reason for this churning of the lake, would have understood that some sudden vent below had set the tide racing to new liberty. But the girls had no such learning in physics. They could only look on in fascinated wonder, in awe. Haphazard, fantastic ideas darted in their brains, vague guesses concerning sea-serpents, earthquakes, tidal waves, waterspouts, which their own native sense rejected. Throughout the experience, neither was able to contrive any explanation of the extraordinary event. They were as confounded at the end as at the beginning.