“What in the name of time is that?” cried Tom, turning a rather alarmed face on the others.

“Indians!” shouted Dick. “We’d better steer clear of here.”

“Idt vos somevuns in pain,” declared the German savant nervously.

Again came the cry. A long shuddering wail that fairly made their flesh creep. They no longer tried to disguise their alarm, but exchanged disquieted looks.

“It is someone suffering pain,” declared Mr. Chadwick. “Better look to your rifles, boys.”

But Captain Sprowl held up his hand to command silence. The grizzled old sailor listened intently for a minute. He was waiting for a repetition of the cry that had so disturbed them.

All at once it came once more,—a moaning, long-drawn sigh this time. It was like the cry of a suffering sinner on his death-bed.

“It’s an awful sound!” shuddered Tom nervously.

“Awful, but blamed human,” put in Captain Sprowl with a sigh of relief, like a gust of wind. “That’s nothin’ more alarmin’ than a sea-cow singin’ her evenin’ song.”