“Ought I to warn her if they return?” Florence asked herself. “Might topple over into the bay. She can’t swim.”

Yet, even as she thought this, Florence smiled at the idea of danger. What if the French girl could not swim? One swimmer was enough. And Florence could swim. Few better. Once she had swum the Ohio river, a mile wide, on a wager.

“Easy to rescue her,” she thought. “But then, why get wet?”

She shuddered at the thought of a plunge. It was August, but the season was late. These northern waters were still cold.

Once more her thoughts shifted. To her right she had caught the gleam of a light. This light suggested mystery. Where the light shone was an island; not much of an island, a pile of rocks overgrown with cedars, but an island all the same. And in the midst of the cedars, dark, mysterious, all but hidden, was a cottage. And in the cottage lived a lady who dressed in somber garments and rowed a black boat. She visited no one, was visited by no one, and was seldom seen save in early morning, or at night. This much Florence had learned by watching the cabin from a distance.

“Mystery!” she whispered. “Of all places, on these northern waters in a community where no man locks his doors. Mystery! Oh, well, probably nothing.”

For all her whispered words, she was convinced that there was something. She meant to find out what that something was.

But now her thoughts were rudely broken off. With a roar that was deafening, the racing speed boat was once more upon them.

Coming closer this time, it set a current of air fanning their cheeks and showered them with fine spray.

The little French girl, waking from her reverie, stared wildly about her, then clutched at the seat. Just in time. The rowboat, rocking violently, threatened to tumble them into the water.