Then, all at once, as if moved by the same set of nerves, they all
turned and fled, for without the slightest warning, a part of the lake
shot up some fifty feet in the air, like some great geyser, but instead
of boiling water it was fluid rock of dazzling brightness even in the
sunshine. Then it fell with a sound of hideous splashing, and as they
turned to gaze back there was a little rising and falling, and then all
was still once more, and the surface rapidly scummed over and grew
silvery and dull.

"I wouldn't have missed this for anything," cried Panton, breaking the
silence as they stood watching the lake, and then, amid many expressions
of wonder and awe at the grandness of the scene, they began to make
their way along the well-defined rim of the crater. But slowly, for
inside there was not a level space, all being a chaos of riven and
scattered masses of slag, obsidian, and scoria, ragged, sharp and in
part glazed by the fluid rock.

"It aren't what I thought it would be, Mr Oliver Lane, sir," said
Smith, scraping the perspiration from his face with a thin piece of the
obsidian which he had picked up, while Wriggs followed his example for a
few moments and then threw his piece down.

"What did you expect?" said Oliver.

"On'y a big hole, sir, running right down into the middle o' the world;
and I thought we should be able to see into the works."

"Works! What works, man!" said Oliver, smiling.

"Why, them as makes the world turn round; for it do turn round, don't
it?"

"Of course, but not from any cause within."

"I say, Tommy, mind what yer at with that there bit o' stuff," growled
Wriggs.

"Why?"

"It's sharp as ragers. I've cut my cheek."

"Sarve yer right for being so clumsy. You should use it like this
here."

"Well, I did, matey."

"I'm blest!" cried Smith, throwing down the piece of volcanic glass, and
dabbing at his nose, whose side was bleeding slightly.

"Cut yoursen?"

"Ay: didn't know it was so sharp as that."

Wriggs chuckled heartily, and the little party moved on as well as they
could for the great fissures about the rim, some of which went down into
profound depths, from whence rose up strange hissings and whisperings of
escaping gases, and breathings of intensely hot air.

There was so much to see, that they would willingly have gone on trying
to follow the edge all round, but before long they had warnings that the
whole of one side was impassable from the vapours