“I’m coming over again,” continued the other. “I hate to let that clever rascal get away; and we must try to pick him up. Hold steady now.”

The transfer was made without any accident, though both boats careened wildly under the strain, thanks to their sharp keels, fashioned only with an eye to making speed.

“I see him, sir!” cried George, as he once more started his engine, and began to curve around the now stationary Flash.

Jack could also readily pick up the swimmer. Evidently Glenwood must have kicked off his shoes, and divested himself of coat and vest, before jumping overboard; for he was making splendid progress through the water, using a hand-over-hand stroke.

This necessitated more or less churning of the water, however, and since the moon persisted in playing into the hands of his enemies by staying out steadily, his course was readily seen.

They bore down rapidly upon him, once the boat had been turned around. But Jack knew only too well that a strong and desperate swimmer would be apt to give his pursuers a hard pull before they could get him. If Glenwood knew his business, as seemed evident, he would hold himself in readiness to duck under, just when they thought to reach over and grasp him.

“Now, steady while I nab him!” said the revenue man, leaning over the bow.

“He’s gone under, sir!” cried Jack, who was holding on to that serviceable boathook, with the idea that possibly he might find a chance to get it fast in the garments of the man in the water.

“Yes, I expected that,” replied the other. “And of course we don’t know just where he’ll come up again. Our only chance is to keep him going until even his iron muscles weaken. We hold the advantage, boys. Look on that side, Jack, and I’ll take care of this. George, be ready to work around or back up, as the case may be.”

Ten seconds later and Jack called out: