As we progressed, the temperature increased in the most extraordinary degree, and I began to feel as if I were bathed in a hot and burning atmosphere. Never before had I felt anything like it. I could only compare it to the hot vapor from an iron foundry, when the liquid iron is in a state of ebullition and runs over. By degrees, and one after the other, Hans, my uncle, and myself had taken off our coats and waistcoats. They were unbearable. Even the slightest garment was the cause of extreme suffering.
"Are we ascending to a living fire?" I cried; when, to my horror and astonishment, the heat became greater than before.
"No, no," said my uncle, "it is simply impossible, quite impossible."
"And yet," said I, touching the side of the shaft with my naked hand, "this wall is literally burning."
At this moment, feeling as I did that the sides of this extraordinary wall were red hot, I plunged my hands into the water to cool them. I drew them back with a cry of despair. "The water is boiling!" I cried.
My uncle, the Professor, made no reply other than a gesture of rage and despair. Something very like the truth had probably struck his imagination.
An invincible dread took possession of my brain and soul. I could only look forward to an immediate catastrophe, such a catastrophe as not even the most vivid imagination could have thought of. An idea, at first vague and uncertain, was gradually being changed into certainty. It was so terrible an idea that I scarcely dared to whisper it to myself. Yet all the while certain, and as it were, involuntary observations determined my convictions. By the doubtful glare of the torch, I could make out some singular changes in the granitic strata; a strange and terrible phenomenon was about to be produced, in which electricity played a part. Then this boiling water, this terrible and excessive heat? I determined as a last resource to examine the compass.
The compass had gone mad! Yes, wholly stark, staring mad. The needle jumped from pole to pole with sudden and surprising jerks, ran round, or as it is said, boxed the compass, and then ran suddenly back again as if it had the vertigo.