d among the bare boughs, but at last Dick softly
pushed his shoulder against Albert's. Albert nodded again, with
comprehension. A small dark animal came into the open space
around the Annex. The boys had difficulty in tracing his
outlines at first, but once they had them fixed, they followed
his movements with ease. He advanced furtively, stopping at
intervals evidently both to listen and look. Some other of his
kind, or not of his kind, might be on the same quest and it was
his business to know.

"Is it a fox?" whispered Albert.

"I think not," replied Dick in the same tone. "It must be a
wolverine. He scents the good things in the Annex and he wants,
oh, how he wants, the taste of them!"

The little dark animal, after delicate maneuvering, came close up
to the tree, and they saw him push his nose against the
cold bark.

"I know just how he feels," whispered Albert with some sympathy.
"It's all there, but he must know the quest is hopeless."

The little animal went all around the tree nosing the cold bark,
and then stopped again at the side of the door.

"No use, sir," whispered Albert. "That door won't open just
because you're hungry."

The little animal suddenly cocked up his head and darted swiftly
away into the shadows. But another and somewhat larger beast
came creeping into the open, advancing with caution toward the
Annex.

"Aha!" whispered Dick. "Little fellow displaced by a bigger
one. That must be a wild cat."

The wild cat went through the same performance. He nosed
eagerly at the door, circled the tree two or three times, but
always came back to the place where that tempting, well-nigh
irresistible odor assailed him. The boys heard a low growl
and the scratching of sharp claws on the door.

"Now he's swearing and fighting," whispered Albert, "but it will
do him no good. Save your throat and your claws, old fellow."

"Look, he's gone!" whispered Dick.

The wild cat suddenly tucked his tail between his legs and fled
from the opening so swiftly that they could scarcely see him go.

"And here comes his successor," whispered Albert. "I suppose,
Dick, we might call this an arithmetical or geometrical
progression."

An enormous timber wolf stalked into the clear space. He bore no
resemblance to the mean, sneaking little coyote of the prairie.
As he stood upright his white teeth could be seen, and there was
the slaver of hunger on his lips. He, too, was restive,
watchful, and