"That I can't say," replied Oliver; "deep enough if you could look straight down. Here, Smith, let's have the ladder. Will it reach?"

The two men came up with the light ladder and pushed it across to find that it was long enough to act as a bridge with a couple of feet to spare.

"But it looks too risky," said Drew, while the two sailors glanced at each other and scratched their heads as they wondered whether one of them would be sent forward to try the ladder's strength.

"Yes, it looks risky," said Oliver, coolly, "but we have to do it."

"No, no," said Panton warmly, "it is too bad. I was disposed to chaff you, Lane, because you threw the hatchet a little about your adventures.

It would be madness to cross that horrible rift."

"Hear, hear," said Smith, in an undertone.

"As aforesaid," said Wriggs.

"We're going across there," said Lane, coolly. "It's the nearest way up and only needs care."

"But, oh! poof!" exclaimed Drew, "you can smell a horrible reek coming up."

"Yes, that's what we keep getting puffs of as we climb. Give me the end of that coil of line, Smith."

"Ay, ay, sir."

"Will it bear me?"

"Half a dozen o' your sort, sir. It's quite noo."

"Good," said Oliver, securing the end tightly about his chest.

"Then you're going to venture?" said Panton.

"Of course, and you're all coming, too. But you'll hold the line and if the ladder breaks or I slip off, you'll hang on and drag me out?"

"Of course. But--"

"Never mind the buts," said Oliver, smiling, and just then, piqued by his companion's banter, he would have crossed had the danger been far greater.

"I say," cried Drew, "won't the sides crumble in from under the ladder?"

"Not likely," said Oliver, coolly; "there's a little ash at the edges, but just below it is solid lava rock."

"Yes, that's so; and this is a huge crack formed in the cooling," said Panton.

"Ready!" cried Oliver. "Hold the rope so that there is no drag upon me, but be ready to tighten."

No one spoke, and Oliver walked to the ladder, placed one foot upon a round, leaned forward, and looked down.

"You can see here," he said, without turning his head, "it goes down till all is black darkness. Now then, let the rope slide through your finger. Ready?"

"Yes, all right."

Then, to the horror of all, instead of going down upon hands and knees, and crawling across, Oliver stepped boldly on upright from round to round, till he reached the centre, where he stopped short, for the slight poles of the ladder had given and given, sinking lower, till it seemed as if they must break. Oliver knew it well, and had stopped short, expecting to feel the check of the rope, which grew moist in the hands which involuntarily tightened around it. The party in safety watched with starting eyes, and breath held till, after a pause of some seconds, which appeared to be prolonged into minutes, the bending ladder began to spring and creak again, as, with his balance regained, Oliver stepped on, round by round, and then reached the other side. Only about a dozen feet, but to all it seemed like a horrible, long journey of the greatest peril.

"Lane, lad," cried Panton, excitedly, as soon as his friend was over, "what madness to go like that!"

"Shouldn't have thought me a coward and a boaster, then," said Oliver, sitting down about three yards from the edge of the chasm, and unfastening the rope from about his chest. "But it isn't safe to come like that; I nearly lost my balance, the ladder bends so. Besides, it will bear you better if you distribute your weight and come on all fours."

"It's not safe even to do that," said Drew, sharply.

"As aforesaid," grumbled Wriggs.

"Oh, yes," said Oliver, smiling, "you can fasten the rope around you Alpine fashion, and I shall hold one end; the others will hold the second end, so that we shall all have you safely enough."

"All right," said Drew, shortly, and he made a loop, pa.s.sed it over his head and shoulders, tightened it, and advanced.

"Now then, draw in the line."

This was done, and with Oliver sitting with his heels firmly against a projection of the rock, and hauling in foot by foot, and the others giving, Drew went down on hands and knees, gripped the sides of the ladder, and crawled across, the wood cracking a good deal, but not bending nearly so much.

"There," said Oliver, as Drew unfastened the rope, "now you can help me hold, and Panton can come over."

"I'm going to walk across," said Panton, firmly.

"No, you are not, man," cried Oliver; "you will crawl. We must run no risks to-day."

Panton grumbled, but obeyed, crawling across in safety after coming to a standstill in the middle and losing his nerve as he gazed down between the rounds.

Then Wriggs came, and Smith was left to run as much risk as Oliver, for he had only rope holders on the farther side, but he went across boldly enough and without hesitation, the rope being steadily gathered in, and when he was over he took a good grip of the ladder and drew it across as well.

"I beg your pardon, Lane," said Panton, in a voice that only his companion could hear. "It was only banter, but I ought to have known better."

"All right, old fellow," cried his companion. "There, say no more."

The sun was growing intensely hot now, as Smith shouldered the ladder, and they once more started up the slope, which rapidly grew steeper, so stiff indeed was the ascent that Oliver, who led, after trying the zigzag approach and finding it too difficult, bore away to the east, making the ascent more gradual, and as if the intention was to form a corkscrew-like path round the upper part of the mountain.

"We've done wrong," he said, after a couple of hours' struggle upwards, "we ought to have gone to the west, and then by this time we should have been in the shade instead of roasting here."

They had paused to have a bit of lunch and rest, for the heat was intense now, and the cracks or rifts in the mountain slope more frequent, but they were not half the width of that which had been just crossed, and as the party had grown more confident they took each in turn readily enough.

"We must make the best of it now," said Panton, "and I can't help thinking that we are doing right."

"Why?" asked Drew.

"It seems to me that it would be impossible to get up to the crater edge on account of these horrible hot gases which rise from the cracks. We had better aim at getting round to the other side, and looking out from there as high up as we can climb. We shall know then whether the place is an island. What do you say, Lane?"

"The same as you do. I've been thinking so for an hour. You see, the ashes get looser as we climb higher, and the mountain steeper. What looked easy enough from below proves to be difficult in the extreme, and if we go much higher I feel sure that we shall set loose a regular avalanche and begin sliding down altogether."

A quarter of an hour later they started off again somewhat refreshed, but suffering terribly from the volcanic heat radiating from the ashes as well as from that from the sun, but they pressed on steadily, rising higher and gradually getting round the north slope, though the farther they tramped over the yielding ashes, the more they were impressed by the fact that the mountain was ten times greater than they had imagined it from below.

At last, late on in the afternoon, Oliver stopped short.