d he burst it open in
three places. It's ruined."

"Cheer up," said Sahwah. "Consider in what a good cause it perished.
You'd have ruined it sooner or later anyhow, but minus the grand
spectacle Slim made."

"Maybe so," grumbled Katherine, "but I was thinking that perhaps this
one would escape the usual fate. I had a fondness for that skirt."

"Then what did you let him take it for?" asked Hinpoha.

"I didn't give it to him, Sahwah did," replied Katherine.

"Well, you said I might," retorted Sahwah, "and, anyway, I'm as badly
off as you. Mine is finished, too."

"Let's not argue over it," said Gladys hastily. "We're getting as bad as
the twins. We started the business, so let's be game and not let the
boys hear us say anything about the skirts."

"All right," said Sahwah, and the subject was dropped.

"What's this?" asked Hinpoha, as they came to the top of the hill.

"A piece of paper tacked to a tree," said Sahwah. "What does it say?"

They all stopped to read. The only writing on the paper was the legend,
THE DARK OF THE MOON SOCIETY. Above it there were three marks done in
red paint, which gave them a curiously lurid effect. They consisted of a
circle with two diamond-shaped marks underneath it.

"What on earth----!" said Hinpoha.

"Those funny-shaped marks are a blaze," said Sahwah. "It was one of the
number we learned, don't you remember, Hinpoha? I believe it means
'warning,' or something like that. 'Important warning,' that's it. Now I
remember. This message is supposed to read:

"'IMPORTANT WARNING!
THE DARK OF THE MOON SOCIETY.'"

"What on earth is The Dark of the Moon Society?" asked Katherine.

They all shook their heads. "It's something the boys are up to," said
Gladys. "I suppose they are going to play some joke on us in return for
our neat little trick the day we climbed the trees and watched them get
supper. Just watch out, something will be doing before very long."

"Let's find out what it is and get ahead of them," said Katherine, her
eyes beginning to sparkle.

From that time on there was a suppressed feeling of excitement on
Ellen's Isle. The Winnebagos watched every movement the Sandwiches made,
and it seemed that there was something suspicious about the glances that
were constantly being exchanged between the Captain, Slim and the
Bottomless Pitt.

"Those three are at the bottom of it," declared Katherine to the other
girls who wer