It was no easier to descend the mountainside than it had been to come up. Rocks and loose stones were numerous, and it appeared to them that some of the cracks in the surface were wider than before. Once Darry stumbled and fell, and the wind was knocked out of him so completely that the others had to help him up and hold him for a moment. Then they turned in the wrong direction and encountered a bed of half-dried mud into which they sunk up to their shoe tops.
“Hi! this won’t do!” called out Sam, who was in the lead. “We’ll all be stuck like flies on flypaper. We’ll have to go to the right.” And this they did.
Looking back they saw that the lava was now flowing at a greater rate than ever. It hissed and steamed viciously, as if anxious to overtake them. The main flow on their right had divided into two streams and one of these was coming straight for them!
“We must get to the other side of yonder split in the rocks!” cried Professor Strong. “It’s our only hope. Come, boys!” And he urged them before him.
The crevasse he mentioned was a good fifty yards away, and now the lava was approaching with incredible swiftness, like some fiery serpent bent upon their destruction. On and on they sped, until their breath came thick and fast and poor Frank felt on the point of fainting away. The professor caught him by the shoulder and almost dragged him to the edge of the opening.
With the lava at their very heels the boys and Professor Strong made the leap over the wide crevasse. The professor had Frank by the hand and went over in safety with his charge, and the leaps of Mark and Darry were equally successful. But poor Sam, as he started to jump, slipped and fell.
“Help!” cried Sam, and then half fell across the opening, to clutch at the edge of the crevasse with his hands. There was next to nothing to hold to, and he was on the point of dropping out of sight when Mark made a dive for him, followed by Darry. Each caught a wrist in his grasp and pulled with all of his strength, and in a moment more Sam was safe. But the escape had been a narrow one, and the youth was as pale as a sheet.
As the whole party collected on the opposite side of the opening the lava poured into it with an increased hissing and a rapid rising of steam. Then, as the lava struck some water far below, there was a loud report, followed by others.
“Come, we have no time to waste!” went on the professor. “That opening will soon fill up and then the lava will be after us again. We must get down to the ocean without delay.”
Again they went on, this time in an irregular line, each holding on to the others. Frank had a stitch in the side, and so had Darry, but neither dared to complain. They knew it was a run for life.