The professor continued, sure of his ground. He emphasized with his pointer as he went on with the explanation.
“I need hardly show you samples of the seismographic readings,” he said. “No doubt you already have plenty of them in your office, for I understand that you have earlier interested yourself in this problem. But I must make certain comparisons with typical readings to show you the purpose of this model earth here and what it proves.”
He touched the button. Instantly there flashed upon a screen above the model a banded chart, with the spidery scrawling of a seismograph clearly marked upon it.
“This is one of the readings, which have often been duplicated in the last few months, as it appeared in Washington. Now if you will notice, I have placed one of my miniature seismographs on the model at Washington. I have built this earth as accurately as I know how, to reproduce the actual conditions as far as that would be possible. The inside is filled with a viscous mass, simulating the viscosity of the earth. The outer shell is made in proportion, both as to weight and thickness. The oceans, simulated in jelly, are approximately correct. In the model I have also placed powerful magnets in such positions that they roughly represent gravity, attracting toward the center. Unfortunately, I have been unable to overcome the force of the real gravity, but I have compensated for it, and in a measure offset its importance for the purposes of this experiment.
“You will observe, if you look closely, that there is a small opening in the earth on an unexplored and hitherto unknown island in the Japanese Sea. There is another exactly opposite it in a small hypothetical island near South America. These openings are connected by a long tube which passes directly through the center of the model, and through which I will drop this iron bullet when we have got the model to rotating at the proper speed.”
The lights in the laboratory suddenly went out, except for a single bright glow at one side of the globe, which might have represented the sun. The huge model began to revolve. It gained speed rapidly, until a small instrument which Dr. Scott held in his hand gave a sharp click. At that point he kept the speed of the model constant.
“We have now reached a rotation,” he explained, “approximately proportional to that of the. earth, reckoning the size of the model in relation to that of the larger sphere. We have spent much time refining these instruments and insuring the accuracy of this experiment. I will now permit the bullet to drop into the tube, where it will respond to the electro-magnets, being iron, as an object dropping into the real earth would respond to gravity.”
There was a click, a slight train of sliding sounds as of metal touching metal at growing speed, then silence. Dr. Scott turned off the power and brought his earth model gently to a stop. Quickly he took the reading of the tiny seismograph located at Washington and flashed it on the screen, greatly magnified, beside the one already showing there. The similarity between them was apparent.
The Secretary looked at the two readings, then at the model. With a puzzled expression he turned to the scientist.
“You have reproduced the tremor,” he admitted, “but still I do not see. “
Dr. Scott laid down his pointer with an air of patience. “Mr. Secretary,” he said, “you have had a great deal of interest in this problem as an amateur scientist. But it was not in this capacity that I called you here to-day. It was because of your duty as a defender of the Americas.
“In short, I am telling you that certain mysterious and hostile peoples on the other side of the earth, fearing to attack us in the air or on water for reasons I shall explain, have dug a tunnel directly through the hot center of the earth, and at this moment are preparing to land a hostile force in South America, in the first drive of a war which may wipe out all of the white population on both of the American continents, and which may, if they are not careful, destroy the earth as well!”
The Secretary rose, his face red and furious.
“You are joking with me,” he said. “I did not come here for that kind of entertainment. A tunnel through the earth! Impossible!”
“Please, please,” said Professor Scott, standing in front of his guest firmly, “do not be so sure that it is impossible until I have explained further. Impossible for us. yes, I will admit that. But that it was impossible for those people who have so cunningly sought to attack us in this manner it certainly was not, and that I can show you also, if you care to hear.”
The anger of the Secretary was genuine. “My good man,” he exclaimed, “you don’t know what you are saying. If this story ever gets out they will make a worse fool of you than ever before. Please stop this nonsense while you still have a shred of reputation left!
“Your own words have condemned this new theory. What of the tremendous pressure you mentioned a short while ago? Don’t you know that the subsurface pressure of the earth has been pretty accurately calculated for a depth of ten miles, and that only so far down it would be equal to thirty times the crushing strength of the finest steel, and nearly one thousand times that of the strongest stone?
“And what of the heat to which this hypothetical earth-tube would be subjected? You have yourself said that the probable temperature at the center of the earth would be sufficient to melt and render gaseous any known rock. What would this invading force build their tube of, to stand such tremendous heat, supposing for the sake of argument that they had found a way to dig the hole under such impossible difficulties in the first place?”
Dr. Scott smiled.
“Sit down, Mr. Secretary,” he said coolly. “I was coming to that.”
The Secretary made a gesture of resignation. “I will listen,” he said, “but please don’t expect me to believe what you say.”
V
The room grew quiet again. The Secretary of War of the Pan-Americas, charged with the defense and protection of hundreds of millions of persons on two continents, listened quietly but with apparent disbelief when the old scientist continued his explanation.
“If you will remember,” Dr. Scott said, “when the unknown tribes poured out of the Asian wastes to conquer China and later Japan, they were able to succeed against those clever and intelligent peoples, trained in all the arts of war and equipped with the most modern explosives and gases, because of one thing. They were able to build metal breastworks and crawling tanks which appeared able to withstand the highest-powered explosives and the battering action of every gun in the enemy camp.
“They had guns, too, and airplanes like those of the Chinese and Japanese, but with the handling of these they were only moderately expert, and in using them against the opposing forces they were relatively unsuccessful. But though the Chinese and Japs, in combined force, were able to beat them out of the air and off the water, the invading race still came on as inexorably as if there had been no armies to oppose them. In armored cars and tanks they moved across the country, occupying it in metal forts which withstood blast after blast without weakening.
“In short, their success was due to one thing only, in which they were superior to their enemies. That was the possession of a heavy and infinitely strong metallic substance which they had discovered or originated in the closed country from which they came to conquer the East.
“This metal was apparently too heavy to put into the construction of airplanes; hence they were beaten in the air. It was too heavy also to put in battleships; hence they failed also on the sea. But it was of such a nature that they finally erected a bridge across a series of islands to Japan. And once there they succeeded in wiping out or enslaving the whole race, and they closed the East again to Western ideas and commerce.
“The new metal caused a great deal of comment at the time, but since no samples of it were ever secured and since later developments prevented any knowledge of it from reaching our hemisphere, references to it by war correspondents in the newspapers of the period began to be ridiculed, and scientists treated the whole subject as a myth.
“But I tell you now that that metal was not a myth. I have no ide
a what it may be, but I am convinced from private calculations that it is a composition, fashioned in some soft form first, then hardened in place for all time. I am certain that it is able to withstand the tremendous pressure of the interior of the earth and that the heat there does not affect it. I am reasonably convinced, in fact, that it acts as a partial insulator for the heat, and so serves to keep the interior of the passage through the earth cool enough to make life within it possible.”
When Dr. Scott paused there was for a moment no sound in the room. Suddenly a slight tremor could be felt, several times repeated, like the shudders caused by heavy traffic. Two test tubes, standing close together on a bench, chittered together for a second, then ceased.
The Secretary spoke. “Have your researches disclosed any further material?” he asked, in a half-mocking way.
Dr. Scott answered him seriously, overlooking the unbelieving tone.
“A great deal more,” he replied, “and some of it is susceptible to some demonstration upon this miniature earth if you care to have me go further into it.”
Dr. Angell made a gesture of assent. It was evident that he was being interested and convinced against his will.
“Then, without going too much into the methods by which we arrived at these results, let me say that Mr. Henderson and I have decided the location and dimensions of the hole through the earth. While the exact nature of some of the contrivances used by the invaders must of necessity be a bit hypothetical, since we are describing something we have never seen, in the main I am sure that future experience will bear us out.
“We believe that the tunnel has been built from an artificial island in the Japanese Sea to another artificial island in the South Atlantic, not far from the shore of lower South America. This route, as you may see from the globe, passes directly through the center of the earth, cutting the plane of the earth’s rotation at an angle roughly of forty-five degrees.4
“We are also convinced that the tube is about a tenth of a mile in diameter, and being approximately eight thousand miles in length, it displaces about two hundred and twenty-eight cubic miles of substance taken from the earth. Hence the necessity for starting it from an artificial island, which provides an easy method of disposing of all this rock and debris.
“Supposing that the average depth of the oceans at the ends of the tube was one mile, there would be enough material, not counting the natural expansion when brought to the surface, to make two islands, each with an area of about one hundred and fourteen square miles, or a diameter roughly of twelve miles. The island on the western end would have to be built, of course, after the tunnel had been holed through, and material for its construction is probably even now rushing through the earth at inconceivable rates of speed, in the same earth-car these invaders will use later to transport their warriors to the Western Hemisphere. They will build not only islands, but causeways also to the mainland at either end. They will tie together Japan and South America by a continuous land-link through the center of the earth.
“As to the recurring and rhythmic earth tremors; they are the record simply of the progress of the earth-car on its frequent and regular journeys through the earth.5 Not knowing the exact weight of their metallic material, we have been unable to calculate the dimensions of this car, but by analogy and experiment we have come to believe that it is shaped somewhat like my iron bullet, probably pointed at either end. It must be nearly the same diameter as the tube, or about five hundred feet, and for the sake of proportion as well as capacity we believe it to be nearly two thousand feet in length from tip to tip.
“Such a car, passing from one hemisphere to the other across the field of the earth’s rotation at the speed of a falling body, would produce the tremors noticed everywhere by seismographs and would be able to make the journey, theoretically, in about 38.47 minutes, with little or no aid except the force of gravity.”
The Secretary raised his hand suddenly. “You are wrong there,” he said. “The force of gravity ceases to exist at the center. Therefore your imaginary car would stop at that point and hang suspended in the middle of the earth!” He continued triumphantly:
“All directions would be up’ to it, and the tunnel would be as effectively plugged as if cubic miles of dirt had been poured into it to fill it up.”
Dr. Scott smiled patiently.
King, who had stepped out of the alcove, where he had been directing the apparatus, broke into the discussion.
“You have forgotten the force of inertia,” he corrected. “In a vacuum, and in the absence of friction, the tremendous momentum acquired by the heavy car by the time it reaches the center will be exactly sufficient to drive it against gravity to the other side of the earth, where it would rise to a point exactly corresponding in distance from the center to that from which it started.”
“Of course you are not asking me to believe that your Asians have been able to overcome friction and interference from the air,” demanded the Secretary.
“No,” replied Dr. Scott. “But with this tremendously heavy car, they probably find it necessary to apply relatively little power to bring the load completely through the earth each time. The nature of the power they use we have no means of knowing, of course. But they have heat enough; it may be that they have learned to turn the heat of the earth directly into propulsive force.”
“What about this terrific speed?” objected the Secretary. “If there were both friction and air resistance working against the passage of the car, such speed would be impossible. The heat produced would burn the earth-car up.”
“Exactly,” Dr. Scott agreed. “I did not say the earth-car actually travels through the earth in thirty-nine minutes. That is the theoretical figure, arrived at by the familiar formula for calculating the speed and time of a falling body. The actual time taken by the Asian car is somewhat over two hours, as any analysis of the seismographic reports will show you. This is still an enormous speed, and one which must produce a prodigious amount of heat. I have no doubt but that they find it necessary to resort to artificial cooling.”
The Secretary arose with an impatient gesture.
“I have many questions,” he said, “and I have no doubt you could answer them if I had time to amuse myself further with this discussion. But I have really important matters to attend to, my dear Doctor. Thank you for an extremely pleasant and unusual afternoon.”
Dr. Scott dropped the curtain over his model and turned to his guest with a flushed face.
“I had no idea that I could convince you,” he said evenly, “but still I felt that it was up to me to do what I could. There is an old adage: Forewarned is forearmed.’ I wanted to prepare you for what I am certain you will learn in a few days. weeks at the most. I wanted you to get ready your defenses against these people before they become too strongly entrenched. I tell you, once they get their breastworks and fortifications up, all hell won’t be able to blow them off their artificial island, and it will take more ingenuity and power than the Japs and Chinese had to keep them from taking the whole Western Hemisphere.”
The Secretary smiled icily. “Thank you, Doctor, for your great interest in this matter,” he replied.
He walked slowly toward the door, accompanied by his aides. Anna opened it for him, and he paused a moment to speak to her.
“I hope we shall meet again. under other circumstances,” he said pleasantly.
She made no reply, but closed the door firmly after him.
“That fool,” exclaimed Dr. Scott. “He’ll be back here before long, apologizing. The worst of it is, we’ll have to help him!”
VI
It was without surprise, but with a great deal of excitement, that Dr. Scott read the headlines of a newspaper on the afternoon of January 14, ten days after the visit of the Secretary of War. The newspaper carried the announcement that a steamer had sighted “unusual volcanic disturbances” in the waters off the coast of southern South America, and that she had herself been crippled in an explosion there.
The story, radioed from Montevideo, said:
“The steamer San Barleyduc, carrying passengers and freight along the coast here, reported to-day about seventy-five miles off shore that it had sighted unusual volcanic disturbances,’ and that upon going closer to investigate she had been struck by debris which tore a huge hole in her bow. Five liners, two of them several hundred miles away, are hurrying to the rescue, but fears are felt for the 320 passengers and crew of the steamer, which is reported to be sinking fast. Navy cutters have been ordered out of base here to aid in the rescue.
“According to the radio received from the San Barleyduc’s captain, the volcanic manifestations are taking place upon a small island, hitherto uncharted, which seems to be growing near latitude 36 south, longitude 55 west, almost in the mouth of the bay. At the center of this island is a huge mushroom-shaped shield, said to be metallic in appearance, but probably composed of smoke.
“Under this shield from time to time the ship saw puffs of vapor, accompanied by violent disturbances in the water. Near the edge of the island new land seemed to be coming up from under the sea, especially on the northwest side, nearest the mainland, where a long finger had already begun to reach out in the general direction of this city.
“The San Barleyduc drew as near as it dared, and the officers scanned the whole performance through glasses. Little more could be learned because of the tremendous clouds of vapor over the new island and in the general region. The weather here has been unusually rainy and cloudy the past few weeks, and it is thought that the phenomena observed by the San Barleyduc may have something to do with it.
“As the officers of the steamer watched, they saw what appeared to be a beak or spout at the edge of the mushroom shield turn toward them. Suddenly there was a terrific explosion, and the ship was covered with a shower of heavy rocks, many of them very hot. Three members of the crew were killed outright, and many passengers were injured. It was found that one rock, apparently weighing many tons, had pierced the metal hull of the ship, and she was going down by the bow.
The Earth-Tube Page 3