[Illustration:  “He moved it out bodily and looked behind and beneath it.”]

“It’s gone,” he said, in an amazed voice.

“Gone?” repeated Prudence.  “What has gone?”

“The map,” said the captain, tumbling his beard.  “I put it in this end pigeon-hole the other night after showing it and I haven’t touched it since; and it’s gone.”

“But you burnt it!” said Prudence, with an astonished laugh.

The captain started.  “No; I was going to,” he said, eyeing her in manifest confusion.

“But you said that you had,” persisted his niece.

“Yes,” stammered the captain, “I know I did, but I hadn’t.  I was just looking ahead a bit, that was all.  I went to the bureau just now to do it.”

Miss Drewitt eyed him with mild reproach.  “You even described how you did it,” she said, slowly.  “You said that Mount Lonesome turned into a volcano.  Wasn’t it true?”

“Figure o’ speech, my dear,” said the unhappy captain; “I’ve got a talent for description that runs away with me at times.”

His niece gazed at him in perplexity.

“You know what Chalk is,” said Captain Bowers, appealingly.  “I was going to do it yesterday, only I forgot it, and he would have gone down on his knees for another sight of it.  I don’t like to seem disobliging to friends, and it seemed to me a good way out of it.  Chalk is so eager—­ it’s like refusing a child, and I hurt his feelings only the other day.”

“Perhaps you burnt it after all and forgot it?” said Prudence.

For the first time in her knowledge of him the captain got irritable with her.  “I’ve not burnt it,” he said, sharply.  “Where’s that Joseph?  He must know something about it!”

He moved to the foot of the staircase, but Miss Drewitt laid a detaining hand on his arm.

“Joseph was in the room when you said that you had burnt it,” she exclaimed.  “You can’t contradict yourself like that before him.  Besides, I’m sure he has had nothing to do with it.”

“Somebody’s got it,” grumbled her uncle, pausing.

He dropped into his chair and looked at her in consternation.  “Good heavens!  Suppose they go after it,” he said, in a choking voice.

“Well, it won’t be your fault,” said Prudence.  You haven’t broken your word intentionally.”

But the captain paid no heed.  He was staring wild-eyed into vacancy and rumpling his grey hair until it stood at all angles.  His face reflected varying emotions.

“Somebody has got it,” he said again.

“Whoever it is will get no good by it,” said Miss Drewitt, who had had a pious upbringing.

“And if they’ve got the map they’ll go after the island,” said the captain, pursuing his train of thought.

“Perhaps they won’t find it after all,” said Prudence.

“Perhaps they won’t,” said the captain, gruffly.

He got up and paced the room restlessly.  Prudence, watching him with much sympathy, had a sudden idea.