an hour we were standing upon the surface of a rock jammed in across the chimney from one side to the other.
Hans pulled the rope by one of its ends, the other rose in the air; after passing the higher rock it came down again, bringing with it a rather dangerous shower of bits of stone and lava.
Leaning over the edge of our narrow standing ground, I observed that the bottom of the hole was still invisible.
The same manœuvre was repeated with the cord, and half an hour after we had descended another two hundred feet.
I don’t suppose the maddest geologist under such circumstances would have studied the nature of the rocks that we were passing. I am sure I did trouble my head about them. Pliocene, miocene, eocene, cretaceous, jurassic, triassic, permian, carboniferous, devonian, silurian, or primitive was all one to me. But the Professor, no doubt, was pursuing his observations or taking notes, for in one of our halts he said to me:
“The farther I go the more confidence I feel. The order of these volcanic formations affords the strongest confirmation to the theories of Davy. We are now among the primitive rocks, upon which the chemical operations took place which are produced by the contact of elementary bases of metals with water. I repudiate the notion of central heat altogether. We shall see further proof of that very soon.”
No variation, always the same conclusion. Of course, I was not inclined to argue. My silence was taken for consent and the descent went on.
Another three hours, and I saw no bottom to the chimney yet. When I lifted my head I perceived the gradual contraction of its aperture. Its walls, by a gentle incline, were drawing closer to each other, and it was beginning to grow darker.
Still we kept descending. It seemed to me that the falling stones were meeting with an earlier resistance, and that the concussion gave a more abrupt and deadened sound.
As I had taken care to keep an exact account of our manœuvres with the rope, which I knew that we had repeated fourteen times, each descent occupying half an hour, the conclusion was easy that we had been seven hours, plus fourteen quarters of rest, making ten hours and a half. We had started at one, it must therefore now be eleven o’clock; and the depth to which we had descended was fourteen times 200 feet, or 2,800 feet.
At this moment I heard the voice of Hans.
“Halt!” he cried.
I stopped short just as I was going to place my feet upon my uncle’s head.
“We are there,” he cried.
“Where?” said I, stepping near to him.
“At the bottom of the perpendicular chimney,” he answered.
“Is there no way farther?”
“Yes; there is a sort of passage which inclines to the right. We will see about that tomorrow. Let us have our supper, and go to sleep.”
The darkness was not yet complete. The provision case was opened; we refreshed ourselves, and went to sleep as well as we could upon a bed of stones and lava fragments.
When lying on my back, I opened my eyes and saw a bright sparkling point of light at the extremity of the gigantic tube 3,000 feet long, now a vast telescope.
It was a star which, seen from this depth, had lost all scintillation, and which by my computation should be 46; Ursa minor. Then I fell fast asleep.
CHAPTER XVIII.
THE WONDERS OF TERRESTRIAL DEPTHS
At eight in the morning a ray of daylight came to wake us up. The thousand shining surfaces of lava on the walls received it on its passage, and scattered it like a shower of sparks.
There was light enough to distinguish surrounding objects.
“Well, Axel, what do you say to it?” cried my uncle, rubbing his hands. “Did you ever spend a quieter night in our little house at Königsberg? No noise of cart wheels, no cries of basket women, no boatmen shouting!”
“No doubt it is very quiet at the bottom of this well, but there is something alarming in the quietness itself.”
“Now come!” my uncle cried; “if you are frightened already, what will you be by and by? We have not gone a single inch yet into the bowels of the earth.”
“What do you mean?”
“I mean that we have only reached the level of the island. long vertical tube, which terminates at the mouth of the crater, has its lower end only at the level of the sea.”
“Are you sure of that?”
“Quite sure. Consult the barometer.”
In fact, the mercury, which had risen in the instrument as fast as we descended, had stopped at twenty-nine inches.
“You see,” said the Professor, “we have now only the pressure of our atmosphere, and I shall be glad when the aneroid takes the place of the barometer.”
And in truth this instrument would become useless as soon as the weight of the atmosphere should exceed the pressure ascertained at the level of the sea.
“But,” I said, “is there not reason to fear that this ever-increasing pressure will become at last very painful to bear?”
“No; we shall descend at a slow rate, and our lungs will become inured to a denser atmosphere. Aeronauts find the want of air as they rise to high elevations, but we shall perhaps have too much: of the two, this is what I should prefer. Don’t let us lose a moment. Where is the bundle we sent down before us?”
I then remembered that we had searched for it in vain the evening before. My uncle questioned Hans, who, after having examined attentively with the eye of a huntsman, replied:
“Der huppe!”
“Up there.”
And so it was. The bundle had been caught by a projection a hundred feet above us. Immediately the Icelander climbed up like a cat, and in a few minutes the package was in our possession.
“Now,” said my uncle, “let us breakfast; but we must lay in a good stock, for we don’t know how long we may have to go on.”
The biscuit and extract of meat were washed down with a draught of water mingled with a little gin.
Breakfast over, my uncle drew from his pocket a small notebook, intended for scientific observations. He consulted his instruments, and recorded:
“Monday, July 1.
“Chronometer, 8.17 a.m.; barometer, 297 in.; thermometer, 6° (43° F.). Direction, E.S.E.”
This last observation applied to the dark gallery, and was indicated by the compass.
“Now, Axel,” cried the Professor with enthusiasm, “now we are really going into the interior of the earth. At this precise moment the journey commences.”
So saying, my uncle took in one hand Ruhmkorff’s apparatus, which was hanging from his neck; and with the other he formed an electric communication with the coil in the lantern, and a sufficiently bright light dispersed the darkness of the passage.
Hans carried the other apparatus, which was also put into action. This ingenious application of electricity would enable us to go on for a long time by creating an artificial light even in the midst of the most inflammable gases.
“Now, march!” cried my uncle.
Each shouldered his package. Hans drove before him the load of cords and clothes; and, myself walking last, we entered the gallery.
At the moment