“No.  The doctor and Molly were both out to lunch—­and you know we only planned this trip this morning.  I haven’t seen them since.  Why do you ask?”

“Because, if they know, they’d send over in search of us if we didn’t turn up in the course of the next hour or so.  But if they don’t know where you are, we stand an excellent chance of spending the night here.”

The gravity of what had first struck her as merely an amusing contretemps suddenly presented itself to Sara.

“Oh!—!” She drew her breath in sharply.  “What—­what on earth shall we do?”

“Do?” Garth spoke with grim force.  “Why, you must be got off the island somehow.  If not, you’re fair game for every venomous tongue in the town.”

“Would any one hear us from the shore if we shouted?” she suggested.

He shook his head.

“No.  The sound would carry in the opposite direction to-day.”

“Then what can we do?”

By this time the manifest anxiety in Trent’s face was reflected in her own.  The possibility that they might be compelled to spend the night on Devil’s Hood Island was not one that could be contemplated with equanimity, for Sara had no illusions whatever as to the charitableness of the view the world at large would take of such an episode—­however accidental its occurrence.  Unfortunately, essential innocence is frequently but a poor tool wherewith to scotch a scandal.

“There is only one thing to be done,” said Garth at last, after fruitlessly scanning the waters for any stray fishing-boat that might be passing.  “I must swim across, and then row back and take you off.”

“Swim across?” Sara regarded the distance between the island and the shore with consternation.  “You couldn’t possibly do it.  It’s too far.”

“Just under a mile.”

“But you would have the tide against you,” she urged.  The current off the coast ran with dangerous rapidity between the mainland and the island, and more than one strong swimmer, as Sara knew, had lost his life struggling against it.

She looked across to the further shore again, and all at once it seemed impossible to let Garth make the attempt.

“No! no!  You can’t go!” she exclaimed.

“You wouldn’t be nervous at being alone here?” he asked doubtfully.

She stamped her foot.

“No!  Of course not!  But—­oh!  Don’t you see?  It’s madness to think of swimming across with the tide against you!  You could never do it.  You might get cramp—­Oh!  Anything might happen!  You shan’t go!”

She caught his arm impetuously, her eyes dilating with the sudden terror that had laid hold of her.  But he was obdurate.

“Look there,” he said, pointing to a faint haze thickening the atmosphere.  “Do you see the mist coming up?  Very soon it will be all over us, like a blanket, and there’d be no possibility of swimming across at all.  I must go at once.”