We assured him it was absolutely correct. He only weighed seventeen pounds.
"Oh, howly Mother of Mercy!" yelled Flathootly. "Consumption has me by the back of the neck. I've lost a hundred and sixty pounds in three days. Oh, sir, for the love of heaven, take me back to me mother. I'm kilt entoirely."
It was some time before Flathootly could understand that his lightness of weight was due to the lesser-sized world he was continually arriving upon, together with centrifugal gravity, and that we all suffered from his affliction of being each "less than half a man" as he termed it. The weighing of the weights wherewith he had weighed himself proved conclusively that the depreciation in gravity applied equally to everything around us.
The extreme lightness of our bodies, and the fact that our muscles had been used to move about ten times our then weight, was the cause of our wonderful buoyancy.
The sailors began leaping from the ship to a large rock that rose out of the water about half a mile off. Their agility was marvellous, and Flathootly covered himself with glory in leaping over the ship hundreds of feet in the air and alighting on the same spot on deck again.
Their officers and scientific staff remained on deck as became their dignity, although tempted to try their agility like the sailors.
Flathootly surprised us by leaping on a yardarm and exclaiming: "Gintlemen, I tell ye what it is, I'm no weight at all."
"How do you make that out?" said the professor.
"Well, Oi've been thinking," said he, "that, as you say, we're in the middle of the two wurrlds. Now it stands to sense that the wan wurrld, I mane the sun up there, is pullin' us up an' the t'other wurrld is pullin' us down, an' as both wurrlds is pulling aqually, why av corse we don't amount to no weight at all. How could I turn fifteen summersaults at wance if I was any weight? That shows yer weighing machine is all wrang again."
"How can you stand on the deck if you are no weight?" inquired the professor.
"Why, I'm only pressing me feet on the boards," said the Irishman; "look here!" So saying, he leaped from the yard and revolved in the air at least twenty times before alighting on the deck.
"Now," said the professor, "I'll explain why you only weigh seventeen pounds as indicated by the spring-balance. We have sailed, down the gulf 500 miles, haven't we?"
"Yis, sorr."
"And here we are sailing upside down on the inside roof of the world – "
"Sailin' upside down? Indeed, sorr, an' ye can't make me believe that, for shure I'm shtandin' on me feet like yourself, head uppermost."
"Well, whether you believe it or not, we are sailing upside down, just as ships going to Australia sail upside down as compared with ships sailing the North Atlantic. But the point of gravity is this: Here we are surrounded on all sides by the shell of the earth, which attracts equally in all directions. Hence all objects in the interior world have no weight as regards whatever thickness of the earth's shell surrounds them. You see, weight is caused by an object having the world on one side of it. Thus both the world and the object attract each other according to the density and distance apart. What we call a pound weight is a mass of matter attracted by the earth on its surface with a force equal to the weight of sixteen ounces. A pound weight on the surface of the earth weighs sixteen ounces, and all the mighty volume of our planet, with all its mountains, continents and seas, weighs only sixteen ounces on the surface of a pound weight. The earth may still weigh many millions of tons as regards the sun, but as regards a pound weight it only weighs sixteen ounces."
"That is an illustration of Flathootly's mental calibre," said Captain Wallace. "He only believes what his brain can accommodate in the way of knowledge."
"God bless the captain," said Flathootly, "I'm shure his brain is as big as mine any day in the week."
"Now," continued the astronomer, "it seems to me that the substances of the earth, rocks, metals, and water, have, under the influence of centrifugal gravity, massed themselves very thickly at the equator or point of greatest motion, and stretch toward the poles in a gradually-lessening mass until the polar gulfs are reached. Thus the earth's shell resembles a musk-melon with the inside cleaned out."
"It makes me mouth wather to think of it," said Flathootly.
"Now, listen," said the astronomer; "we are also under the influence of the earth's centrifugal motion, and wherever we are on the interior surface we swing round our circle of latitude in twenty-four hours, and thus men, ship, and ocean are held up against the interior vault like a boy being able to hold water in a vertical position at the bottom of the pail he swings round him at the end of a cord."
"Don't you think, professor," I inquired, "we will become heavier as we approach the region of greatest motion under the equator?"
"I don't think so," he replied, "for the ocean around the poles has naturally gravitated to the internal as well as to the external equator, to restore the equilibrium of gravity. The reason why a man does not weigh less on the external equator than at the poles, although flying around at the rate of a thousand miles an hour, is that the deeper ocean, that is, the extra twenty-six miles that the earth is thicker on the equator, counter balances by its attraction the loss of weight due to the rapid centrifugal motion, and so preserves in all objects on the earth a uniform weight."
"The whole thing," said Flathootly, "is as clear as mud. I'm glad to know, sorr, I haven't lost me entire constitution at all evints, an' if I can only carry home what weight I've got lift I'll make a fortune in a dime museum."
CHAPTER IX.
AFLOAT ON THE INTERIOR OCEAN
As the Polar King sped southward over the interior sea the wonders of the strange world we had discovered began to dawn upon us. The colossal vault rose more and more above us and the sun threw his mild and vertical rays directly upon ship and sea, producing a most delightful climate. The ocean had a temperature of 75 degrees Fahr. and the air 85 degrees. We were absolutely sailing upside down to an inhabitant of the outer sphere, yet we seemed to ourselves to be sailing naturally erect on the sea with the sun above us.
Our first experience in the internal sphere was that of a sudden storm. The sun grew dark and appeared like a disc of sombre gold. The ocean was lashed by a furious hurricane into incredible mountains of water. Every crest of the waves seemed a mass of yellow flame. The internal heavens were rent open with gulfs of sulphur-colored fire, while the thunder reverberated with terrible concussions. The ship would spin upon the water as though every wave were a whirlpool. A golden-yellow phosphorescence covered the ocean. The water boiled in maddening eddies of lemon-colored seas, while from the hurricane decks streamed cataracts of saffron fire. The lightning, like streaks of molten gold, hurled its burning darts into the sea. Everything bore the glow of amber-colored fire. The sailors congratulated themselves on the shelter provided by the deck overhead. The motion of the ship exceeded all former experiences, for it leaped and plunged in a terrific manner. It was a question whether we would survive the storm or not, so violent was the shaking up both ship and men received. Fortunately, the loss of weight in everything, which was the cause of the rapid motion, permitted no more damage than would be caused by a lesser storm on heavier objects.
The professor stated that he believed the tempest was occasioned by a polar tidal wave of air rushing into the interior sphere, to supply the exhaustion caused by outgoing warm currents, owing perhaps to a periodical overheating of the air by the internal sun. When a certain volume of the air was expelled, so that it could no longer resist external pressure, then the external air rushed down the polar gulf, creating by meeting warm outward-flowing currents cyclones such as we were then experiencing.
By degrees the storm abated, the sea grew calm, the heavens above us became clearer, and the sun assumed the rose-color he first presented to our gaze, standing right in the zenith.
The only damage done to the crew was a few broken limbs and some severe bruises. The ship had lost several spars, and one of her boats was blown out of its lashings on deck and was lost.
It was a week since we had left the outer world, and what a change had occurred in that short space of time! The excitement had been