"I've got to get him out alone," decided Mark. "But how can I do it?"

He crawled cautiously nearer to the edge of the extinct volcano and
looked down. A few loose stones, dislodged by his weight, rattled down
the sides.

"Look out!" cried Jack quickly, "or you'll fall, too!"

"I'll be careful," answered Mark, and then he drew away out of danger,
with a queer feeling about his heart, which was beating furiously. Mark
had hoped to be able to make his way down the side of the crater to
where his chum was and help him up. But a look at the steep sides and
the uncertain footing afforded by the loose rocks of lava-like
formation showed that this could not be done.

"I've got to think of a different scheme," decided Mark, and, spurred
on by the necessity of acting quickly if he was to save Jack, he fairly
forced his brain to work. For he saw by the strained look on his chum's
face that Jack could not hold out much longer.

"I have it!" cried Mark at length. "My fur coat! I can cut it into
strips of hide and make a rope. Then I can lower it down to Jack and
haul him up."

He did not think, for the moment, of the cold he would feel when he
stripped off the fur garment, and when it did come to him in a flash he
never hesitated.

"After all, I've often been out without an overcoat on cold days," he
said to himself. "I guess I can stand it for a while, and when Jack is