"Hold on, Alvin," whispered the other; "let's play a trick on that fellow that keeps nosing into our business."

"How?"

"Let's use his boat to get a closer view of the Deerfoot."

It was a rash thing to do, but it appealed to the young Captain.

"All right; I'm with you. We must hurry, for he is likely to come back any moment."

Had they taken time for reflection, they probably would have given up the plan, but boys of their age and younger are not apt to "look before they leap." Without hesitation, they walked to where the frail boat lay against the bank and Alvin shoved it clear. The water seemed to be deep close to land, and the Captain took up the paddle, remarking that the craft bore some resemblance to a canoe. They half expected that the man would dash forward and call them to account, but nothing was seen or heard of him, and the gloom swallowed them from sight of any person on land.

Now that the chance was theirs to settle the question which had perplexed them so long it was important to consider each step. Alvin had had experience in managing a small boat and he handled the paddle with more skill than the former occupant, for the ripple which he caused could not have been heard a dozen feet away. As the distance from shore increased, they ceased to whisper. One knew the right thing to do as well as the other, and Chester realized that he could give no directions of value.

It seemed to Alvin that since those on the launch knew the direction taken by one of their number, they would expect him to return over the same course. Instead, therefore, of making straight for the motor boat, the Captain turned to the right, so as to approach the bow or stern. Before he caught sight of the craft, he made a complete circuit of the islet, keeping just near enough to trace its outlines and that of the launch. The former was merely a mass of sand, consisting of about an acre and without a tree or shrub upon it. It must have been nearly submerged when the tide was high.

Seated in the prow of the small boat, Chester Haynes peered with all the power of eyesight at his command into the darkness, partly lighted up now and then by the moon. This made the illumination treacherous and uncertain and caused misgivings to both. Alvin glanced up at the rolling clouds, striving to avoid betraying himself to anyone on board. The presumption was that all had gone to sleep, leaving the duty of protection to their friend, the man in gray.

A look at the masses of vapor in the sky told Alvin that the heavy obscurity would last for several minutes. He dipped the paddle deeper and stole toward the bow of the launch that was beginning to show vaguely. By and by he saw the sharp cutwater rising several feet above the water, the staff with its drooping flag, and the glass shield just aft of the motor compartment.