“I think,” said Mr. Bruce to Mr. Graham, who was following him, “that we will have to walk right through this mountain, and on to the end of the crevice, when we can turn and climb the cliff from the back, which I expect to find of easy ascent.”

“I quite agree with you,” said Mr. Graham. “It is quite certain that there could be no way of reaching the summit from this crevice; at least, not at this point.”

“It has taken a powerful stirring up of the internal fires to cause this fearful crack,” said Mr. Bruce.

“Yes,” said Mr. Graham, “and that volcano looks as if it might throw out something more than dust and ashes very soon.”

“That it will, and sooner than we will want it to,” replied Mr. Bruce. “We are treading dangerous ground, and we cannot tell what moment we may be overtaken by a flow of molten lava, or a greater shower of ashes, such as buried Pompeii.”

“But,” said Mr. Graham, “if we stop to think of such things, we will not do a great deal of exploring.”

“No,” said Mr. Bruce, “but it is always best to bear these things in mind, and be ready at any moment to meet them as well as we can under the circumstances. But I can scarcely see my way here. Were any torches brought along?”

“Yes, the attendants have torches,” said Mr. Graham.

It was true; at this point the crevice was so deep one might think it was night, so dark had it grown. The torch was lighted, and Mr. Bruce, taking it, they all again took up the march. But from this point the path began to widen and ascend, until they were not only again in the sunlight but two could walk abreast, and a little further, and the path had widened until four and five men could walk abreast. The path ascended gradually, so gradually that it was not difficult to climb, and in a short while it ran out even with the surface.

This was a great and pleasant surprise to the explorers, for they had expected to have to tramp much farther before getting out of the hole. They looked about them and saw that they were on the side of a lofty mountain, the cliff opposite being but a precipitous side of the same mountain. This side was very fertile and wooded with great trees almost to its summit.