DURING the course of his inventive life Roland Clewe had become accustomed t_isappointments; he was very much afraid, indeed, that he was beginning t_xpect them. If that really happened, there would be an end to his career.
But when he spoke in this way to Margaret, she almost scolded him.
"How utterly absurd it is," she said, "for a man who has just discovered th_orth pole to sit down in an arm-chair and talk in that way!"
"I didn't discover it," he said; "it was Sammy and Gibbs who found the pole.
As for me—I don't suppose I shall ever see it."
"I am not so sure of that," she said. "We may yet invent a telescope whic_hall curve its reflected rays over the rotundity of the earth and above th_ighest icebergs, so that you and I may sit here and look at the waters of th_ole gently splashing around the great buoy."
"And charge a dollar apiece to all other people who would like to look at th_ole, and so we might make much money," said he. "But I must really go and d_omething; I shall go crazy if I sit here idle."
Margaret knew that the loss of the shell was the greatest blow that Roland ha_ver yet received. His ambitions as a scientific inventor were varied, but sh_as well aware that for some years he had considered it of great importance t_o something which would bring him in money enough to go on with hi_nvestigations and labors without depending entirely upon her for th_ecessary capital. If he could have tunnelled a mountain with this shell, o_f he had but partially succeeded in so doing, money would have come to him.
He would have made his first pecuniary success of any importance.
"What are you going to do, Roland?" said she, as he rose to leave the room.
"I am going to find the depth of the hole that shell has made. It ought to b_illed up, and I must calculate how many loads of earth and stones it wil_ake to do it."
That afternoon he came to Mrs. Raleigh's house.
"Margaret," he exclaimed, "I have lowered a lead into that hole with all th_ine attached which we have got on the place, and we can touch no bottom. _ave telegraphed for a lot of sounding-wire, and I must wait until it shal_rrive before I do anything more."
"You must be very, very careful, Roland, when you are doing that work," sai_argaret. "Suppose you should fall in!"
"I have provided against that," said he. "I have laid a floor over the hol_ith only a small opening in it, so there is no danger. And another curiou_hing I must tell you-our line is not wet: we have struck no water!"
When Margaret visited the Works the next day she found Roland Clewe and _umber of workmen surrounding the flooring which had been laid over the hole.
They were sounding with a windlass which carried an immense reel of wire. Th_ire was extremely thin, but the weight of that portion of it which ha_lready been unwound was so great that four men were at the handles of th_indlass.
Roland came to meet Margaret as she entered.
"The lead has gone down six miles," he said, in a low voice, "and we have no_ouched the bottom yet."
"Impossible!" she cried. "Roland, it cannot be! The wire must be coilin_tself up somewhere. It is incredible! The lead cannot have gone down so far!"
"Leads have gone down as far as that before this," said he. "Soundings of mor_han six miles have been obtained at sea."
She went with him and stood near the windlass. For an hour she remained by hi_ide, and still the reel turned steadily and the wire descended into the hole.
"Shall you surely know when it gets to the bottom?" said she.
"Yes," he answered. "When the electric button under the lead shall touc_nything solid, or even anything fluid, this bell up here will ring."
She stayed until she could stay no longer. She knew it would be of no use t_rge Roland to leave the windlass. Very early the next morning a note wa_rought to her before she was up, and on it was written:
"We have touched bottom at a depth of fourteen and an eighth miles."
When Roland came to Mrs. Raleigh's house, about nine o'clock that morning, hi_ace was pale and his whole form trembled.
"Margaret," he cried, "what are we going to do about it? It is wonderful; _annot appreciate it. I have had all the men up in the office this morning an_ledged them to secrecy. Of course they won't keep their promises, but it wa_ll that I could do. I can think of no particular damage which would come t_e if this thing were known, but I cannot bear that the public should get hol_f it until I know something myself. Margaret, I don't know anything."
"Have you had your breakfast?" she asked.
"No," he said; "I haven't thought of it."
"Did you eat anything last night?"
"I don't remember," he answered.
"Now I want you to come into the dining-room," said she. "I had a ligh_reakfast some time ago, and I am going to eat another with you. I want you t_ell me something. There was a man here the other day with a patent machin_or making button-holes—you know the old-fashioned button-holes are coming i_gain—and if this is a good invention it ought to sell, for nearly everybod_as forgotten how to make button-holes in the old way."
"Oh, nonsense!" said Roland. "How can you talk of such things? I can't take m_ind—"
"I know you can't," she interrupted. "You are all the time thinking of tha_verlasting old hole in the ground. Well, I am tired of it; do let us talk o_omething else."
Margaret Raleigh was much more than tired of that phenomenal hole in the eart_hich had been made by the automatic shell; she was frightened by it. It wa_omething terrible to her; she had scarcely slept that night, and she neede_reakfast and change of thought as much as Roland.
But it was not long before she found that it was impossible to turn hi_houghts from that all-absorbing subject. All she could do was to endeavor t_uide them into quiet channels.
"What are you going to do this morning?" she asked, towards the close of th_reakfast.
"I am going to try to take the temperature of that shaft at various points,"
"That will be an excellent thing," she answered; "you may make valuabl_iscoveries; but I should think the heat at that great depth would be enoug_o melt your thermometers."
"It did not melt my lead or my sounding-wire," said he. And as he said thes_ords her heart fell.
The temperature of this great perforation was taken at many points, and whe_oland brought to Margaret the statement of the height of the mercury at th_ery bottom she was astounded and shocked to find that it was only eighty- three degrees.
"This is terrible!" she ejaculated.
"What do you mean?" he asked in surprise. "That is not hot. Why, it is onl_ummer weather."
But she did not think it terrible because it was so hot; the fact that it wa_o cool had shocked her. In such temperature one could live! A great source o_rust and hope had been taken from her.
"Roland," she said, sinking into a chair, "I don't understand this at all. _lways thought that it became hotter and hotter as one went down into th_arth; and I once read that at twenty miles below the surface, if the hea_ncreased in proportion as it increased in a mine, the temperature must b_ver a thousand degrees Fahrenheit. Your instrument could not have registere_roperly; perhaps it never went all the way down; and perhaps it is all _istake. It may be that the lead did not go down so far as you think."
He smiled; he was becoming calmer now, for he was doing something: he wa_btaining results.
"Those ideas about increasing heat at increasing depths are old-fashioned, Margaret," he said. "Recent science has given us better theories. It is know_hat there is great heat in the interior of the earth, and it is also know_hat the transmission of this heat towards the surface depends upon th_onductivity of the rocks in particular locations. In some places the hea_omes very near the surface, and in others it is very, very far down. Mor_han that, the temperature may rise as we go down into the earth an_fterwards fall again. There may be a stratum of close-grained rock, possibl_ontaining metal, coming up from the interior in an oblique direction an_ringing the heat towards the surface; then below that there may be vas_egions of other rocks which do not readily conduct heat, and which do no_riginate in heated portions of the earth's interior. When we reach these, w_ust find the temperature lower, as a matter of course. Now I have really don_his. A little over five miles down my thermometer registered ninety-one, an_fter that it began to fall a little. But the rocks under us are poo_onductors of heat; and, moreover, it is highly probable that they have n_ear communication with the source of internal heat."
"I thought these things were more exact and regular," said she; "I supposed i_ou went down a mile in one place, you would find it as hot as you would i_nother."
"Oh no," said he. "There is nothing regular or exact in nature; even our eart_s not a perfect sphere. Nature is never mathematically correct. You mus_lways allow for variations. In some parts of the earth its heated core, o_hatever it is, must be very, very far down."
At this moment a happy thought struck Margaret.
"How easy it would be, Roland, for you to examine this great hole! I can d_t; anybody can do it. It's perfectly amazing when you think of it. All yo_ave to do is to take your Artesian, ray machine into that building and set i_ver the hole; then you can light the whole interior, all the way down to th_ottom, and with a telescope you can see everything that is in it."
"Yes," said he; "but I think I can do it better than that. It would be ver_ifficult to transfer the photic borer to the other building, and I can ligh_p the interior perfectly well by means of electric lights. I can even lower _amera down to the very bottom and take photographs of the interior."
"Why, that would be perfectly glorious!" cried Margaret, springing to he_eet, an immense relief coming to her mind with the thought that to examin_his actual shaft it would not be necessary for anybody to go down into it.
"I should go to work at that immediately," said he, "but I must have _ifferent sort of windlass—one that shall be moved by an engine. I will rig u_he big telescope too, so that we can look down when we have lighted up th_ottom."
It required days to do all that Roland Clewe had planned. A great deal of th_ecessary work was done in his own establishment, and much machinery beside_as sent from New York. When all was ready many experiments were made with th_lectric lights and camera, and photographs of inexpressible value an_nterest were taken at various points on the sides of this wonderfu_erpendicular tunnel.
At last Clewe was prepared to photograph the lower portion of the shaft. Wit_ peculiar camera and a powerful light five photographs were taken of the ver_ottom of the great shaft, four in horizontal directions and one immediatel_elow the camera. When these photographs were printed by the improved method_hen in vogue, Clewe seized the pictures and examined them with eager haste.
For some moments he stood silent, his eyes fixed upon the photographs as i_here was nothing else in this world; but all he saw on each was an irregula_atch of light. He thrust the prints aside, and in a loud, sharp voice he gav_rders to bring the great telescope and set it up above the hole. The ligh_as still at the bottom, and the instant the telescope was in position Clew_ounted the stepladder and directed the instrument downward. In a few moment_e gave an exclamation, and then he came down from the ladder so rapidly tha_e barely missed falling. He went into his office and sent for Margaret. Whe_he came he showed her the photographs.
"See!" he said. "What I have found is nothing; even a camera shows nothing, and when I look down through the glass I see nothing. It is just what th_rtesian ray showed me; it is nothing at all!"
"I should think," said she, speaking very slowly, "that if your sounding-lea_ad gone down into nothing, it would have continued to go down indefinitely.
What was there to stop it if there is nothing there?"
"Margaret," said he, "I don't know anything about it. That is the crushin_ruth. I can find out nothing at all. When I look down through the earth b_eans of the Artesian ray I reach a certain depth and then I see a void; whe_ look down through a perfectly open passage to the same depth, I still see _oid."
"But, Roland," said Margaret, holding in her hand the view taken of the botto_f the shaft, "what is this in the middle of the proof? It is darker than th_est, but it seems to be all covered up with mistiness. Have you a magnifying- glass?"
Roland found a glass, and seized the photograph. He had forgotten his usua_ourtesy.
"Margaret," he cried, "that dark thing is my automatic shell! It is lying o_ts side. I can see the greater part of it. It is not in the hole it mad_tself; it is in a cavity. It has turned over, and lies horizontally; it ha_ored down into a cave, Margaret—into a cave—a cave with a solid bottom—a cav_ade of light!"
"Nonsense!" said Margaret. "Caves cannot be made of light; the light that yo_ee comes from your electric lamp."
"Not at all!" he cried. "If there was anything there, the light of my lam_ould show it. During the whole depth of the shaft the light showed everythin_nd the camera showed everything; you can see the very texture of the rocks; but when the camera goes to the bottom, when it enters this space into whic_he shaft plainly leads, it shows nothing at all, except what I may be said t_ave put there. I see only my great shell surrounded by light, resting o_ight!"
"Roland," said Margaret, "you are crazy! Perhaps it is water which fills tha_ave, or whatever it is."
"Not at all," said Roland. "It presents no appearance of water, and when th_amera came up it was not wet. No; it is a cave of light."
He sat for some minutes silently gazing out of the window. Margaret drew he_hair closer to him. She took one of his hands in both of hers.
"Look at me, Roland!" she said. "What are you thinking about?"
He turned his face upon her, but said nothing. She looked straight into hi_yes, and she needed no Artesian ray to enable her to see through them int_is innermost brain. She saw what was filling that brain; it was one great, overpowering desire to go down to the bottom of that hole, to find out what i_as that he had discovered.
"Margaret, you hurt me!" he exclaimed, suddenly. In the intensity of th_motion excited by what she had discovered, her finger-nails had nearl_enetrated through his skin. She had felt as if she would hold him and hol_im forever, but she released his hand.
"We haven't talked about that button-hole machine," she said. "I want you_pinion of it." To her surprise, Roland began immediately to discuss the ne_nvention of which she had spoken, and asked her to describe it. He was not a_ll anxious now to tell Margaret what he was thinking of in connection wit_he track of the shell.