e gathered on her bed. "I don't believe the rest of the
Sandwiches know a thing about it. I heard Dan Porter asking the Captain
what they were talking about down on the beach awhile ago and the
Captain said, 'Oh, nothing,' in that tone of voice that means, 'It's
none of your business.'"

"But I saw Slim and Dan and the Monkey slipping off into the woods by
themselves just now," said Sahwah, "and they were laughing to themselves
and acting mighty mysterious."

The next day Hinpoha found a piece of birchbark in Eeny-Meeny's wooden
hand, bearing the now familiar warning blaze and signed with the
initials D. M. S.

"The handwriting on the wall again," she said to Gladys. "What can the
Dark of the Moon Society be, anyhow?"

After that mysterious warnings appeared all over camp. The girls would
find them tacked to the trees in front of their tents, tied to the
handles of the water pails and slipped in between the logs piled ready
for firewood. True to their agreement they never said a word about
finding them to the Sandwiches, but were constantly on the lookout for
the joke, which they knew would be sprung sooner or later. Katherine,
who had flung her indigoes to the winds at the first hint of mystery,
was the most intent on finding out what the boys were planning to do and
meant to get ahead of them if she could possibly do it.

"The thing to do first," said she with the air of a general, "is to find
out which ones are the Dark of the Moon Society. Then we can watch those
particularly."

"They're probably all in it," said Gladys.

"I don't think they are," said Katherine. "I'll lay my wager on the
Captain, Slim and the Bottomless Pitt. Those three are mighty chummy all
of a sudden. And I saw them go right past one of those signs on a tree
and never look at it. That looks suspicious. They saw me and pretended
they didn't notice the sign."

That night, Katherine, restless and unable to sleep, developed a thirst
from rolling around on her pillow, and rising quietly, made for the
water pail at the door of the tent. It was empty. Thirsts had been
prevalent that night. She stood a moment irresolute and then, putting on
her slippers and her gown, started boldly for the little spring on the
hillside. It was bright moonlight and she could find her way easily. She
took a drink from the cup hanging on a broken branch beside the spring,
and filling the pail so as to be prepared for a return of the thirst,
she started back up t