ed. "Girls," she
said in a thrilling whisper, "I've found the place where the Dark of the
Moon Society meets!"

"Where? Where?" they all cried.

"In a cave under the east bluff. I just discovered it today. The
entrance is all covered by trees. I found the ashes of a little fire
inside. That's where they're cooking up their plans and preparing
something to spring as a surprise on us."

"Oh, if we could only hide back in that cave when they are there and
hear and see what they are doing," said Sahwah.

"How are we going to know when they will be there?" asked Gladys.

Nobody was able to answer this.

"If we're smart enough we'll find out," said Katherine, waving her long
arms. She was as keen on the scent of the mysterious Dark of the Moon
Society as a hound after a stag.

That night darkness had hardly fallen when the Captain, Slim and the
Bottomless Pitt complained of being utterly tired out and announced
their intention of going to bed.

"What made you so tired, boys?" asked Mrs. Evans solicitously. "Are we
expecting you young people to do too much? I don't want you to go home
worn out."

"Oh, it was probably from running up and down the path so often with the
boards for the dock," said the Captain. "That's all." He yawned widely
behind his hand. "We're not doing too much every day, really we aren't.
You mustn't feel anxious."

Mrs. Evans made a mental resolve to see that the boys and girls all had
a definite rest hour each day.

Katherine's thoughts went into a widely different channel. At the first
mention of going to bed before the others she became suspicious, and,
looking closely, she was positive that the Captain's yawn was feigned.
Lying on her back on the sand so that her head was behind Sahwah and
Gladys she whispered very quietly, "D. M. S. meeting." Gladys and Sahwah
squeezed her arm to let her know they understood and as soon as the
three boys had started up the hill they rose also, saying they were
going up on the Council Rock. Hinpoha rose and followed them; Migwan and
Nakwisi apparently did not catch on, and remained where they were.

There was no time to follow the boys. The girls must be in the cave
before the Sandwiches got there to be able to overhear anything. Taking
a short cut, they came out on the bluff just above the cave. They could
hear the boys stopping for a drink at the spring on the other side of
the island.

"How'll we get down?" asked Gladys in a whisper.

"Crawl down