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Journey to the Center of the Earth
Chapter 15. WE CONTINUE OUR DESCENT
At eight o'clock the next morning a faint dawn woke us.
The many prisms of the lava caught the light and sent it to us like a shower of sparks.
We could easily see the objects around us.
"Well, Harry, my boy," cried the delighted Professor, rubbing his hands together.
"What say you now?"
"Did you ever pass a more tranquil night in our house in the Konigstrasse?"
"No deafening sounds of cart wheels, no cries of hawkers, no bad language from boatmen or watermen!"
"Well, Uncle, we're quite at the bottom of this well, but to me there's something terrible in this calm."
"Why," said the Professor hotly.
"One would say you were already beginning to be afraid."
"How will you get on presently?"
"Do you know, that as yet, we haven't penetrated one inch into the bowels of the earth."
"What can you mean, sir?" was my bewildered and astonished reply.
"I mean to say that we have only just reached the soil of the island itself."
"This long vertical tube, which ends at the bottom of the crater of Sneffels, ceases here just about on a level with the sea."
"Are you sure, sir?"
"Quite sure. Consult the barometer."
It was true that the mercury, after rising gradually during our descent, had stopped precisely at twenty-nine degrees.
"You perceive," said the Professor, "we have as yet only to endure the pressure of air. I'm curious to replace the barometer by the manometer."
The barometer was becoming useless because the air's weight would soon exceed the value calculated for above sea level.
"But," said I, "is it not very much to be feared that this ever-increasing pressure may not in the end turn out very painful and inconvenient?"
"No," said he.
"We'll descend very slowly, and our lungs will gradually get used to breathing compressed air."
"It's well known that aeronauts have climbed so high they were nearly without air at all."
"Why, then, shouldn't we get used to breathing when we have, say, a little too much of it?"
"For myself, I'm certain I'll prefer it."
"Let's not lose a moment."
"Where is the packet which preceded us in our descent?"
I smiled and pointed it out to my uncle.
Hans hadn't seen it and believed it had caught somewhere above us.
"Huppe" as he put it.
"Now," said my uncle, "let us breakfast, and break fast like people who have a long day's work before them."
Biscuit and dried meat, washed down by a few mouthfuls of water flavored with Schiedam, made our luxurious meal.
As soon as it was finished my uncle took from his pocket a notebook to be filled with notes of our travels.
He had already set his instruments in order and this is what he wrote,
Monday, June 29th, chronometer set at 8:17 as we began our descent.
Chronometer, 8h. 17m. in the morning, exact time noted by the Professor.
Barometer, 29.6 inches, indicated the atmospheric pressure at that time.
Thermometer, 6 degrees, showing the passage was surprisingly cool for so deep underground.
Direction, E.S.E. as indicated by the compass swinging gently in the dim light.
This last observation referred to the dark gallery and was shown to us by the compass.
"Now, Harry," cried the Professor in an enthusiastic tone.
"We're truly about to take our first step into the Interior of the Earth, never before visited by man since the first creation of the world."
"You may consider, therefore, that at this precise moment our travels really commence."
As my uncle said this, he took in one hand the Ruhmkorff coil apparatus that hung round his neck.
With the other hand he put the electric current into connection with the worm of the lantern.
A bright light at once lit that dark and gloomy tunnel!
The effect was magical, lighting the dark tunnel as if by enchantment.
Hans, who carried the second apparatus, switched his on too.
This use of electricity let us move by an artificial daylight, even among the most inflammable and combustible gases.
"Forward!" cried my uncle.
Each took up his burden, Hans went first, my uncle followed, and I went third, and we entered the somber gallery!
About to enter the passage, I looked up through the tubelike shaft and saw the Iceland sky I'd never see again.
Was it the last sky I'd ever see?
The stream of lava that had flowed from the earth in 1219 had forced a passage through the tunnel.
It lined the whole inside with its thick and shining coating.
The electric light added greatly to the brightness of the effect.
The great difficulty of our journey now began.
How were we to stop ourselves from slipping down the steep slope?
Luckily some cracks, worn places in the soil, and other irregularities served as steps.
We descended slowly and let our heavy luggage slide ahead on a long cord.
But what served as steps under our feet became in other places stalactites.
The lava, very porous in some spots, took the form of little round blisters.
Crystals of opaque quartz, with clear drops of natural glass hanging from the roof like lights, seemed to catch fire as we passed beneath them.
One would have thought the genii of romance were lighting their underground palaces to receive the sons of men.
"Magnificent, glorious!" I cried in a moment of involuntary enthusiasm.
"What a spectacle, Uncle! Do you not admire these variegated shades of lava, from reddish brown to pale yellow, and these crystals that appear like luminous globes"?
"You're beginning to see the charms of travel, Master Harry," cried my uncle.
"Wait a bit, until we advance farther. What we have as yet discovered is nothing, onwards, my boy, onwards!"
It would have been more accurate if he had said, "let us slide," for we were going down an inclined plane with perfect ease.
The compass showed we were moving in a southeasterly direction.
The flow of lava had never turned to the right or the left, it kept the straight line.
Yet, to my surprise we found no clear increase in heat.
This proved Humphry Davy's theories to be true, and more than once I found myself checking the thermometer in silent wonder.
Two hours after our start it only marked fifty-four degrees Fahrenheit.
I had every reason to think from this that our descent was much more horizontal than vertical.
As for finding the exact depth we had reached nothing could be easier.
The Professor as he moved measured the angles of deviation and inclination but he kept the result of his observations to himself.
About eight o'clock in the evening my uncle gave the signal to stop.
Hans sat on the ground, the lamps were hung to fissures in the lava rock.
We were now in a large cavern where air wasn't lacking.
On the contrary it was plentiful, What could cause this breeze?
What atmospheric movement could explain this draft?
But I didn't want to discuss it then.
Fatigue and hunger made me unable to reason.
A long march of seven hours had tired me greatly.
I was truly worn out and very happy to hear the word Halt.
Hans laid out some provisions on a lump of lava and we each ate with keen relish.
One thing however caused us much worry.
Our water supply was already half used.
My uncle trusted we'd find underground water but so far we had completely failed to do so.
I couldn't help pointing this out to my uncle.
"And you're surprised at this total absence of springs?" he said.
"Surely. I'm very worried about it. We certainly don't have enough water to last five days."
"Don't worry on that point," my uncle continued.
"I promise we'll find plenty of water, in fact far more than we'll need."
"But when?"
"When we once get through this crust of lava. How can you expect springs to force their way through these solid stone walls?"
"But what proves that this solid mass of lava doesn't extend to the centre of the earth?"
"I don't think we have yet done much in a vertical way."
"What puts that into your head, my boy?" asked my uncle mildly.
"Well, it seems to me that if we had gone very far below the level of the sea we should find it hotter than we have."
"According to your system," said my uncle, "but what does the thermometer say?"
"Hardly fifteen degrees by Reaumur, which is only an increase of nine since our departure."
"Well, and what conclusion does that bring you to?" asked the Professor.
"The deduction I draw from this is simple."
"According to the most exact observations the rise of temperature inside the earth is one degree for every hundred feet."
"But some local causes may change this figure a lot."
"Thus at Yakoust in Siberia it has been noted that the heat increases one degree every thirty-six feet."
"The difference clearly depends on how well certain rocks conduct heat."
"Near an extinct volcano it has been noted that the rise was only one degree in every twenty-five feet."
"Let us then use this calculation which is the most favorable and calculate."
"Calculate away, my boy."
"Nothing easier," said I, taking out my notebook and pencil.
"Nine times one hundred and twenty-five feet make a depth of eleven hundred and twenty-five feet."
"Archimedes couldn't have spoken more geometrically."
"Well?"
"Well, according to my observations we're at least ten thousand feet below the level of the sea."
"Can it be possible?"
"Either my calculation is correct or there's no truth in figures."
The Professor's calculations were perfectly correct, we were already six thousand feet deeper in the earth than anyone had ever been before.
The lowest known depth humans had reached was in the mines of Kitzbuhel in the Tirol and those of Wurttemberg.
The temperature, which should have been eighty-one, was here only fifteen.
This was a serious matter to consider.