My uncle was careful to note every hour the indications of the compass, of the manometer, and of the thermometer, all which he afterward published in his elaborate philosophical and scientific account of our remarkable voyage. He was therefore able to glove an exact relation of the situation. When, therefore, he informed me that we were fifty leagues in a horizontal direction distant from our starting point, I could not suppress a loud exclamation.
“What is the matter now?” cried my uncle.
“Nothing very important, only an idea has entered my head,” was my reply.
“Well, out with it, my boy.”
“It is my opinion that if your calculations are correct we are no longer under Iceland.”
“Do you think so?”
“We can easily find out,” I replied, pulling out the map and compasses.
“You see,” I said, after careful measurement, “that I am not mistaken. We are far beyond Cape Portland; and those fifty leagues to the southeast will take us into the open sea.”
“Under the open sea,” cried my uncle, rubbing his hands with a delighted air.
“Yes,” I cried, “no doubt old ocean flows over our heads.”
“Well, my dear boy, what can be more natural. Do you not know that in the neighborhood of Newcastle there are coal mines which have been worked far out under the sea?”
Now my worthy uncle, the Professor, no doubt regarded this discovery as a very simple fact, but to me the idea was by no means a pleasant one. And yet when one came to think the matter over seriously, what mattered it whether the plains and mountains of Iceland were suspended over our devoted heads, or the mighty billows of the Atlantic Ocean? The whole question rested on the solidity of the granite roof above us. However, I soon got used to the idea, for the passage now level, now running down, and still always to the southeast, kept going deeper and deeper into the profound abysses of Mother Earth.
Three days later, on the eighteenth day of July, on a Saturday, we reached a kind of vast grotto. My uncle here paid Hans his usual rix-dollars, and it was decided that the next day should be a day of rest.
XXII
Sunday below Ground
I awoke on Sunday morning without any sense of hurry and bustle attendant on an immediate departure. Though the day to be devoted to repose and reflection was spent under such strange circumstances, and in so wonderful a place, the idea was a pleasant one. Besides, we all began to get used to this kind of existence. I had almost ceased to think of the sun, of the moon, of the stars, of the trees, houses, and towns; in fact, about any terrestrial necessities. In our peculiar position we were far above such reflections.
The grotto was a vast and magnificent hall. Along its granitic soil the stream flowed placidly and pleasantly. So great a distance was it now from its fiery source that its water was scarcely lukewarm, and could be drunk without delay or difficulty.
After a frugal breakfast, the Professor made up his mind to devote some hours to putting his notes and calculations in order.
“In the first place,” he said, “I have a good many to verify and prove, in order that we may know our exact position. I wish to be able on our return to the upper regions to make a map of our journey, a kind of vertical section of the globe, which will be, as it were, the profile of the expedition.”
“That would indeed be a curious work, Uncle; but can you make your observations with anything like certainty and precision?”
“I can. I have never on one occasion failed to note with great care the angles and slopes. I am certain as to having made no mistake. Take the compass and examine how she points.”
I looked at the instrument with care.
“East one quarter southeast.”
“Very good,” resumed the Professor, noting the observation, and going through some rapid calculations. “I make out that we have journeyed two hundred and fifty miles from the point of our departure.”
“Then the mighty waves of the Atlantic are rolling over our heads?”