it in satisfaction.

"They'll have it so hot they can't get up it for some time yet," he
remarked hopefully.

We shouldered our packs and set out over the wilderness of snow,
turning our backs upon the metal-bound lake of fire, with the tall
cone of iridescent flame rising in its center.

The deep, purple-blue sky was clear, and, for a rarity, there was not
much wind. I doubt that the temperature was twenty below. But it was a
violent change from the warm cavern. Mildred was blue and shivering.

* * * * *

In two hours the metal rim below the great white cone had vanished
behind the black ice-crags. We passed near the wreck of Major
Meriden's plane and reached our last camp, where we had left the tent
sledge, primus stove, and most of our instruments. The tent was still
stretched, though banked with snow. We got Mildred inside, chafed her
hands, and soon had her comfortable.

Then Ray went out and soon returned with a sealed tin of oil from the
wrecked plane, with which he lit the primus stove. Soon the tent was
warm. We melted snow and cooked thick red soup. After the girl had
made a meal of the scalding soup, with the little golden cakes, she
professed to be feeling as well as ever.

"We can fix our plane!" Ray said. "There's a perfectly good prop on
Meriden's plane!"

We went back to the wreck, found the tools, and removed an undamaged
propeller. This we packed on the sledge, with a good supply of fuel
for the stove.

"I'm sure we're safe now, so far as the crab-things go," he said. "I
don't fancy they'd get around very well in the snow."

In an hour we broke camp, and made ten miles of the distance back to
the plane before we stopped. We were anxious about Mildred, but she
seemed to stand the journey admirably; she is a marvelous physical
specimen. She seemed running over with gay vivacity of spirit; she
asked innumerable questions of the world which she had known only at
second-hand from her mother's words.

* * * * *

The weather smiled on us during the march back to the plane as much as
it had frowned on the terrible journey to the cone. We had an
abundance of food and fuel, and we made it in eight easy stages. Once
there was a light fall of snow, but the air was unusually warm and
calm for the season.

We found the plane safe. It was the work of but a short time to remove
the broken propeller and replace it with the one we had brought