“I think it’s going to fit,” he murmured, a world of hope in his voice, though he squinted vigilantly, watchfully, as he continued the twisting. “By Jove, Tom, I believe it’s O. K. It seems fast and tight. I’ll let a little oil in; give the wheel a few turns.”

A few breathless seconds passed. Then the pistons began to move up and down, slowly, all but noiselessly. Seized with a kind of fearful fascination, both motor boat boys watched the engine, almost afraid to breathe lest the driving cease.

Then Captain Halstead, still looking backward, while Joe’s chest heaved at last, yanked himself up into the hatchway, glancing out over the water.

The schooner was now almost upon the “Rocket,” though hauling off a bit to windward as though intending to make a sudden swoop and bear down crushingly against the motor boat.

“Safe?” Halstead almost whispered down into the engine room.

“Try it, awfully easy,” replied Joe.

“Hank, give the speed-ahead control just a bare turn,” called Halstead. “Easy, now!”

The propeller shaft began to revolve. At that same instant the schooner came around on a starboard tack, so steered as to intercept the shorter craft.

Captain Tom himself sprang to the speed control, letting out just a notch more, praying under his breath that the motor might stand by them in this moment of greatest crisis.