“What about that half-breed?” asked Sam.  “I think we’d better find out who he is.  I didn’t like the looks of that fellow a little bit.”

“Neither did I,” agreed George.  “Queer we never saw him around here before.”

“You must remember this is a large lake,” Billy informed them.  “He probably is a fisherman who hangs out on the island, and who resented our encroaching upon his preserves.  I think I saw the same fellow once in a canoe, but he was so far away that I don’t think I would know him were we to meet face to face.”

“There are too many mysterious things on this island,” averred Larry Goheen, with emphasis.  “I, for one, shall be glad to get away from it.  I know there are spooks here.”

“Spooks!” jeered George.  “Who’s afraid of spooks?  Who—­” George’s voice trailed off almost into a whisper.  “I heard something,” he exclaimed.

“So did I,” added Larry, nodding.

A laugh, a distinctly human laugh, shrill and mocking, was wafted to them.  The boys gazed questioningly at each other.  Larry glanced about apprehensively.  Then out of the night came the most weird, most demoniacal laugh any member of the Tramp Club ever had heard.

The boys sprang to their feet.

Other laughs, accompanied by shrieks, followed each other in quick succession.  The laughs seemed to come from all quarters.  It was difficult to say from just what particular point any one of them did come.

“Spooks!” yelled Larry Goheen, bolting toward the lake.  Billy caught and jerked him back.

“No, you don’t,” growled Billy.  “We stand together.”

“I don’t want to stay here,” chattered Larry.  “I never try to fool people with fake courage when I know that running is my one best course to pursue.”

“Is there a lunatic asylum in this part of the country?” asked Baker.  “Can it be possible that any of the inmates have escaped.”

Billy Gordon shook his head.  “Nothing as easy as that,” he sighed.

“Great Scott!  There it goes again!” breathed Larry.  “It’s down that way, too,” pointing in the direction taken by Harriet Burrell.

It was a long, weird wail, well calculated to freeze the marrow in one’s bones.

“Come on, fellows!” cried George, with a fine showing of resolution.  “We’ll lay that ghost!”

George was the only one of the boys who thought to snatch up a club as he ran.  But now the unearthly sounds came from the rear, instead of ahead of them.  The boys wheeled abruptly, only to hear right in front of them a dismaying chorus of ghostly noises.

“Let’s go!” urged Larry.  “It’s surely a lot of banshees!”

“Great Scott!  Look!” quivered Sam, pointing with trembling finger.

In the faint light the boys made out a white figure that might have been anywhere from seven to ten feet in height.  The boys were too scared to judge of length.  The awful thing raised its draped arms, a frightful scream sounding on the air.