most entirely covered
with green moss, among which the clear little fingers of water trickled.

Suddenly a discordant scream rang out. It was so fearful that several of
the fellows turned pale, and all of them started violently.

"There!" ejaculated Chatz.

His manner was almost triumphant; just as though he would like to demand
whether these chums of his could not find some reason to believe as he
did, after such a manifestation.

"Oh, glory, what was that!" quivered Landy, as he clutched the arm of
Elmer Chenowith.

"But it didn't come from the mill," declared Larry. "Sounded to me like
it was out there on the pond."

"Good for you, Larry," remarked Elmer.

"Then I was right?" asked the other.

"You certainly were, and if the whole of you turn your eyes aways up
yonder, perhaps you'll notice a big black-and-white bird come to the
surface. It dived just after scolding us for disturbing its fishing
excursion."

Following the direction indicated by Elmer's extended finger the scouts
all watched eagerly.

"I see something moving just behind that bunch of lily pads," exclaimed
one with keen vision.

"There it swims out now, and it's a big water bird, too. Looks like a
goose to me," Landy remarked, earnestly.

"That's a loon, fellows!" exclaimed Red.

"Is it, Elmer?" they demanded in a breath.

"Just what it is, and nothing else," replied the acting scout master.
"They are very common up in the Great Northwest. And once you've heard
their wild laugh you'll never forget it."

"Huh, sounds just like the shout of a crazy man to me," ventured Lil
Artha.

"Everybody says that," Elmer declared. "And I never knew a single
fellow who liked to hear a loon call. Some say it's a sign of ill luck
to be scolded by a loon."

"Ill luck!" echoed Chatz, once more looking in the direction of the
ramshackle old mill.

"But see here," remarked Matty, "tell us about Nat, won't you? When was
his queer disappearance first noticed, Elmer?"

"Well, when Lil Artha and myself arrived here we found Toby and Ty
throwing stones out in the pond, scaring the little red-marked turtles
that were sitting by dozens on every old log and rock, and great big
bullfrogs as well."

"Never saw so many whopping big frogs in all my life," declared Ty.

"You see," explained Toby, "we missed Nat, but thought he had just
wandered off to look around. Ty and me, why, we felt too tired to
explore things till the rest came along."

"Oh, but you