“No—forward—full speed ahead!” cried Nicky.

Henry had sunk down and covered his eyes from the vision of the black-finned monsters congregating in the muddy waters—sharks!

Bill had the tiller ropes roaring in their channel, for he had paid no heed to the conflicting orders but, with a little prayer of devout trust that he did not mention later, he stood, gripping the spokes.

The boat had lost way, and swung sideways across the rushing water. Tom saw what was coming. Instantly he snatched loose a life preserver! Not to leap and save his life. To save all of them!

He bent low, hanging over the bow, dropping the preserver so that it met the rock, was between it and the boat as she touched.

She shuddered, and there was a crunch, but no smash. Madly yelling for full speed astern, Bill pawed his wheel over; the boat hesitated, her back-lashed propeller striving against the stream; slowly she receded from the rocks. Tom released his clutch on the preserver rope; from aft came the grind and shiver of sickening contact; the engine grated to a stop with a jar and a cough. The boat shuddered, ran forward again in the current.

“The propeller hit!” shouted Cliff, from the after deck, staring overside at a wicked fang, seeming to lick its glistening lips at him.

“It’s probably bent beyond help!” called Andy, from the engine. “The gears in the shift box are stripped. When the propeller caught it tore the gear teeth off—lucky it didn’t crack the crankshaft!”

“But we have no power,” ruefully Bill called.

There was no use for it, had they possessed it. With the strong outsweep of the water, and with a low, sandy spit jutting before them, there was nothing to be done but wait.