The Earth-Tube (6 page)

“Steam!” he declared. “I have it now. they are using steam to build their island! They hurl the rocks and earth with terrific force from that steam-gun there,” he explained, “and send tons of them through the air to any desired location.”

The Secretary looked at him incredulously.

“And there’s the answer to your weather problem,” the scientist continued. “They are using the heat of the earth to turn vast quantities of sea water into steam. The vapor naturally condenses after it has been released into the air and returns to the sea as rain and mist.”

“But they can’t possibly build that causeway all the way to land by such crude methods,” objected the Secretary. “It’s all of seventy-five miles from this spot to the nearest point on shore.”

The professor readily agreed. “It’s likely,” he said, “that they will soon build an extension of the shield over the causeway, covering it for protection. Then the soil will be passed along underneath, probably by some rapid mechanical means, until the causeway is completed. You will find, in a few days, that the pathway from the Eastern Hemisphere to South America has been completed and fully armored from the island to the shore.

“Then will begin the steady conquest of the continents, proceeding upon the slow treads of caterpillar tanks and movable metal fortresses.”

Secretary Angell turned away. “Oh, professor,” he replied, “don’t surrender the continents so easily!”

“But I am not surrendering them,” the scientist corrected. “I am only writing the history in advance for you. The onerous duty of surrendering, I’m afraid, will fall upon your portfolio!”

The five planes, with their convoy, sailed around the edges of the metal shield, observing what they could of conditions below them. Little was to be seen which had not already been described. Dr. Scott calculated that the metal covering was resting upon supports which perched it at least half, and perhaps three-quarters of a mile in the air. Beneath it there would be room to house an army of men, in addition to the necessary gear for “landing” the inter-hemispheric car and launching it upon the return journey.

“It is likely,” Dr. Scott observed, “that the Asians have more than one of these cars. From the frequency with which the trips are made, I believe they have at least three; one at either end being loaded while a third is in the tube. The regularity of the earth-tremors caused by these flying monsters makes it fairly evident that there are no long delays at either end, such as would certainly be occasioned if it were necessary to unload and reload the one car each time between journeys. But with a loaded car waiting at either end, the schedule of about two hours per trip could be kept up indefinitely and with express-like regularity.”

The fliers, remembering the fate of the plane which had flown into the air blast on the day before, stayed well away from the center of the shield. From the behavior of the clouds it was evident that there was a tremendous stream of air rising there again, and in addition there was a curious rumbling which could be heard even above the drone of the airplane motors and the whistle of wind. It had the full-throated sound of a noise issuing from an immensely deep well, but it was also an unmistakably metallic clatter. a series o-f long, sliding, ringing sounds.

Dr. Scott listened to them closely, trying to catch the timing and the rhythm as the noise rapidly increased. Touching the sleeve of the Secretary, he called his attention also to the thunder roaring upward from the earth beneath the dome.

“If you will listen,” he remarked, “you’ll hear the earth-car coming with its load. It can’t be far away. It may arrive at any minute now!”

The scientists and technicians were visibly excited at this announcement. The planes were slowed and ordered to circle as near the center of the mushroom as was safe. The power was partly shut down, so that the rumble, now increased to the thunder of a Niagara, could be heard plainly.

The wind whistled up from the opening at a fearful rate, and all around the edge of the metallic shield there were curious puffs and eddies of steam. So great was the tumult that the earth appeared to be trembling. The sea at the edges of the island was broken into a choppy, foaming mass, thundering against the rocks with peculiar fury.

Louder and louder came the noise, rising to an overwhelming crescendo. Suddenly a great jet of steam appeared in the middle of the island. There was a loud clang, like the sound of many metal partitions jangling against one another. A long, metallic nose appeared in the opening in the shield and rose upward for perhaps a hundred feet, its gleaming surface lustrous with heat and polished surfaces. The red eye of the sun, bursting for a moment from the fetters of clouds, flashed upon it once and became muffled again. The metal nose dropped back a little way, inclined to one side, and disappeared in a violent blast of steam, which seemed in an instant to overwhelm the whole island, blotting it from sight.

Dr. Scott, when he saw the menacing billow of vapor rising underneath, was suddenly electrified.

“Full power ahead, and climb, climb!” he screamed into the control room. The engineers had seen the danger also. The motors roared, and the propellers, hurled abruptly into top speed, tore at the air, pulling the huge plane after them.

The other official planes, when they saw the scalding steam, also started away to escape. The five machines, like startled birds, darted swiftly upward as the white demon engulfed the world beneath with a tremendous whistling noise.

But several of the lighter planes found themselves unable to get away. The rolling cloud caught and smothered them. The condensing vapor as it rose turned into jets of scalding rain, which stopped the tardy motors and cooked the luckless pilots in their seats.

King and the Secretary stared with horror at the phenomenon. Thousands of tons of water, converted into steam, had been thrown into the air at them. It was like a nightmare, the race for safety from the menacing cloud. Every ounce of power in the motors was thrown on. The sturdy frames of the planes groaned and shuddered, strained to the utmost.

At an altitude of three miles the cloud was still coming viciously upward toward them, but the alarmed pilots saw with relief that it was coming more slowly than at first and that they had gained enough distance to permit them to pull off sidewise and defeat the steam. The plane which carried the scientists zoomed eastward with a sudden turn. The white arms of the demon momentarily obscured the windows and the cabin. The occupants thought for a minute that the game was up, and then, abruptly, the blue sky appeared overhead. They were saved.

Underneath the still skyward-reaching cloud behind them there was a terrific downpour of warm rain, so heavy as almost to preclude flying into it. The few small planes which had managed to escape the scalding cloud circled away off and finally turned for home to report this new manifestation and to refuel. The five official ships, which were sturdy and fully equipped for many more hours of continuous flying, headed bravely into the downpour and circled back toward the island again. On the sea, when they came close, they perceived the wreckage of several unlucky planes, but there was no sign of life about any of them.

“I take it you are convinced now that we have a powerful and ingenious people to deal with,” said Dr. Scott to the Secretary, who was visibly shaken by the ordeal through which they had just passed.

“Yes,” was the reply, “but there are many things that want explaining, it seems to me. Why, for instance, all that outburst of steam? Did it mean that they were taking that unique means of destroying us?”

“Hardly,” replied the scientist. “I am quite sure, in fact, that they do not even know we are here, unless by accident they have sighted us. The steam came from the interior of the earth, following the car, whose nose we saw as they were landing her.

“Don’t you see. to overcome gravity, friction, and the pressure of the air, and also, no doubt, to hasten the passage of the car, they have turned their tube into a huge steam engine! They have heat enough. free heat. in the center of the earth. They have water enough, in the oceans. Consequently, after the car has gone a certain distance they perhaps seal the tube at some point and turn the water in. The resulting steam blows the car out the other end like a piston in a steam engine. It is only necessary to reverse the process to send the same car, or another, back again.”

“And the tremendous clattering we heard?”

“A projectile, traveling as fast as this one does, need only touch the side walls with the slightest whisk from time to time to produce what would seem like a constant noise like that, echoed up out of the depths of so long a well. The car is nearly the same diameter as the tube, but enough smaller, probably, so as not too greatly to increase the friction and air resistance. I have no doubt that it is equipped with rollers or other friction reducing bearings along the sides, in anticipation of just such striking in the tube.”

“But why need it touch the side walls at all?” asked the Secretary. “If these fellows are the perfect engineers you say, why couldn’t they launch it straight into the tunnel and let it pass through without striking?”

“That is simply explained,” replied Dr. Scott. “Such a car will, of necessity, touch upon one side or the other of the earth-tube throughout the journey, with the exception of a brief interval at the center. This is due to the rotation of the earth, which at the surface, at the equator, moves eastward at the rate of about one thousand miles an hour.

“This speed is correspondingly less toward the poles, which do not move at all, of course. Therefore it must be somewhat more than six hundred miles an hour at the mouth of the earth-tube. As the car approaches the center of the earth the influence of rotation becomes proportionally less, and the pressure against the side of the tube decreases with it.

“Crossing the center, the car encounters the earth
moving in the opposite direction,
and must adjust itself to this new condition, sliding against the wall of the tube under constantly increasing pressure until the mouth is reached.”

The planes were over the island again. The rain was still falling heavily, but the air was clearer because the clouds of vapor had largely blown away. They could see the general outlines of the entire island. It was evident that already another car had been launched downward through the tube. Above the center of the shield, where the jet of upward-rushing air had formerly been, there was now a tremendous sucking, and a funnel of cloud and water was being carried directly down into the hole from the heavy layers of mist above. It looked like a slender thread being pulled from a tangled skein and wound upon an unseen bobbin underneath the earth.

“When the projectile has reached a certain point,” Dr. Scott commented, “they will probably seal the tube and turn the water in. Until then, it might as well be filling up with air, which also expands rapidly under the action of heat.”

The Secretary smiled mysteriously.

“Well,” he said, “this is all very amusing, and I have no doubt your Asians are an ingenious race, but I don’t know any reason why we should permit this invasion’ to go any farther. In fact, I believe I’ll put an end to it right now.”

Dr. Scott glanced at him questioningly. King had a sudden premonition. But it was too late. The Secretary had given a signal, which was flashed to the other planes almost at the same instant.

“What are you doing?” demanded King. Dr. Angell, without answering, waved his hand toward the four other planes of the investigating party. They had drawn off a little and were circling low over the metal shield, near the edge.

Suddenly there was a series of terrific flashes, accompanied by a continuous roar that shook the air and caused the official plane to vibrate like a cork caught upon turbulent water. A tiny wisp of smoke cleared away from the gleaming surface beneath the circling fliers, but no change was visible there.

With great agitation the Secretary stared at the shield beneath the planes through his field glasses, turning them this way and that. The four bombers had dropped enough high explosives upon the shining dome to sink a fleet of battleships, but there was not even a mark or discoloration upon the metal where the bombs had struck.

“Well,” growled Dr. Scott with great exasperation, “I suppose it was
your
plan to have them bomb that shield.”

The Secretary answered in a shaky voice. For the first time he appeared to be realizing the seriousness of the invasion from the other side of the world.

“I ordered them to drop the explosive,” he admitted nervously, “but it is clear, the bombs did nothing.”

“Nothing to the shield, you mean,” corrected the scientist. “But they undoubtedly warned the Asians that we have spotted them and tried to blow them out. If you had not tried this foolish trick we might have worked out some wiser means of attack and caught them unaware.

“But from now on they’ll be prepared. You’ve declared war on them, and they’ll soon give you war a-plenty. You can count on that!”

III

The Asians made their first attack on Montevideo. In a perfectly matter-of-fact way they finished their causeway, as Dr. Scott had prophesied, by passing material along it, underneath an armored covering of metal which reached out into the ocean to the earth-tube cap and joined it. They extended it to the nearest point on the coast of Uruguay,
⁶
and repelled every attempt to interrupt their work with such blasts of steam and rock that shipping in that region was almost paralyzed. Steamers plying between Buenos Aires, Montevideo, and other southern ports and the north were forced to make a wide circuit around the island, coming into the bay from the southward.

The War Department’s first move was to mount heavy coast defense artillery at the point where the causeway was expected to strike land, and to keep up a ceaseless bombardment. Their shots only added debris to the mountains of rock which the Asians, by their own devices, were hurling there. Whenever a shell struck the overhead covering of the finished causeway it bounded off like a pea or exploded harmlessly. The work of building the land connection was neither slowed nor deflected by the artillery. The Asians did not even do the War Department the honor to return the gunfire. The work of finishing the link between the island and the shore was carried on as impersonally as if, indeed, the entire phenomenon was of volcanic and natural origin, despite the evidences of guiding intelligence manifest in the nature of the construction.