"Come over and look at it," Dick went on. "No one could live
in this cold place. It is chilling me to the bone, just to stand
here. And now you see why that little trickle of water keeps
moving out through the mouth of the cave. Fellows, we're in one
of nature's icehouses."

"But we're not after ice," Dave protested.

"We won't turn down ice in the wilderness, when we can find it
in July," Dick rejoined.

"Not much!" answered practical Tom Reade. "Why, fellows, ice is
just what we need at the camp. Let's get a closer look at it
and make plans for an ice-box over at the camp."

"But I want to follow that man of mystery," protested Dave.

"Go ahead, David, little giant," Dick laughed. "We won't stop
you. But we've lost our man of mystery, anyway, and this cave
contains something that we really do want. Tom, you're the
mathematician of the party. How much ice is there here?"

"If I could see better I could tell you better," sniffed Reade.
"Hundreds of tons of it, anyway."

"How did the stuff get here?" asked Dan wonderingly.

Dick was now at the edge of the ice pile, and flashed the light
at the roof of the cavern.

"See the rifts in the rock up there?" he asked. "Water must have
leaked in here during the heavy winter rains. It was cold water,
too. Then, in extra cold spells, such as this country experiences,
the water must have frozen. As heat doesn't get in here in warm
weather the ice may have been here for generations. Fellows,
we may be looking upon ice that was here when George Washington
was a boy."

"I've read, somewhere," declared Tom soberly, "that icebergs that
float down from the polar regions in spring often represent ice
that is at least ten thousand years old. Fellows, some of this
very ice may have been here in this cave long, long before Julius
Caesar went into the soldiering business!"

That thought had somewhat of an awesome effect upon Dick & Co.
The four high school boys felt as though they were in the presence
of great antiquity.

"But the practical side of it," declared Tom, "is that we must
devise the best way of cutting some of this ice and getting it
across the lake to the camp."

"Oh, you can break off enough for making ice water," replied Dave
Darrin impatiently, "and take it over in the canoe, though the
spring water is cold enough for anybody."

"All of Dave's thoughts are still on the man of mystery," Dick
declared, with a chuckle.

"It's much more inter