"But if they lap us round!" I angrily replied.
"They will not lap us round," was his quiet and serene answer.
"But it will be all the same in the end if they stifle us," I cried.
"We shall not be stifled. The gallery is rapidly becoming wider and wider, and if it be necessary, we will presently leave the raft and take refuge in some fissure in the rock."
"But the water, the water, which is continually ascending?" I despairingly replied.
"There is no longer any water, Harry," he answered, "but a kind of lava paste, which is heaving us up, in company with itself, to the mouth of the crater."
In truth, the liquid column of water had wholly disappeared to give place to dense masses of boiling eruptive matter. The temperature was becoming utterly insupportable, and a thermometer exposed to this atmosphere would have marked between 189 and 190 degrees Fahrenheit. Perspiration rushed from every pore. But for the extraordinary rapidity of our ascent we should have been stifled.
Nevertheless, the Professor did not carry out his proposition of abandoning the raft; and he did quite wisely. Those few ill-joined beams offered, any way, a solid surface—a support which elsewhere must have utterly failed us.
Towards eight o'clock in the morning a new incident startled us. The ascensional movement suddenly ceased. The raft became still and motionless. "What is the matter now?" I said, querulously, very much startled by this change.
"A simple halt," replied my uncle.
"Is the eruption about to fail?" I asked.
"I hope not."
Without making any reply, I rose. I tried to look around me. Perhaps the raft, checked by some projecting rock, opposed a momentary resistance to the eruptive mass. In this case, it was absolutely necessary to release it as quickly as possible.
Nothing of the kind had occurred. The column of cinders, of scoriæ, of broken rocks and earth, had wholly
