"Oh, Mark, can't you save me?" he gasped. "Call Professor Henderson!"
"I'll get you up, don't worry!" called Mark, as confidently as he could. "Hold tight, Jack. What has become of your life-torch?"
"I have it here by me. I didn't drop it, and it's on a piece of the rock near my head. Otherwise I couldn't breathe. Oh, this place is fearfully deep. I guess it hasn't any bottom."
"Now, keep still, and don't think about that. Save your strength, hold fast, and I'll get you up."
But, having said that much, Mark was not so sure how next to proceed. It was going to be no easy task to haul up Jack, and that without ropes or other apparatus. Another matter that added to the danger was the necessity of keeping the life-torch close to one's face in order to prevent death by the poisonous gases.
Mark's first impulse was to hasten back and call the two professors, but he looked over the desolate landscape, and could not see them, and he feared that if he went away Jack might slip and fall into the unknown depths of the crater.
"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.