But let me pass from this subject, for the present, to mention some of the astonishing facts I learned under her tutorage. First, of course, there was the necessity of studying the native language; but, fortunately, I made rapid steps in this direction, not so much because of any natural ability, as for the fact that Loa was a capable teacher, and because I made every effort to remember when she pointed to object after object and mentioned its native name, and then, after a time, began linking the words into simple sentences. I was like a little child first learning the language of its parents; but having, I confidently believe, a quicker intelligence than a child's, I was not long in absorbing the rudiments of the vernacular. Within two or three weeks, I could exchange elementary ideas; within a month, I could conduct a brief conversation; while, in less than three months, I was able to carry on an extended colloquy with any member of Tan Trum's household, and would not miss more than an occasional word, due to the limits of my vocabulary.
Strange, unbelievably strange, were my discoveries as to my new home. The underworld, composed of the twin countries of Wu and Zu, reached for hundreds of miles in all directions, and probably underlay not only most of Nevada, but much of Utah, Arizona, and adjoining states. This whole vast universe, comprising a multiplicity of great caverns and smaller connecting galleries, some of which reached down eight or ten miles, was inhabited by a population variously estimated as between forty and fifty millions—all of them chalk-faced and salmon-eyed, like the ones I had already seen. Neither Loa nor her father could tell me how long they had dwelt underground; their written records dated back thousands of years, and their claim was "Forever"! While there were traditions that once they had lived above ground, in a land of blue skies and open air from which they had been driven to escape annihilation in warfare, there were now no intelligent men to believe such tales, which were not only preposterous on the surface, but had never been proven by historical research. It was generally held that human life had originated in caves underground, and that, as population multiplied, men had excavated new caves and corridors to take care of the surplus millions.
So accustomed had the people become to their subterranean environment that it was impossible for them to appear above ground, unless they wore heavy metallic suits, like those of undersea divers, in order to protect them from the rays of the sun, which their white skins, having lost all pigment in the course of the ages, were no longer able to endure. Hence their belief, which scientists had verified by means of elaborate mathematical proofs, that no life could endure above ground, and hence the fact that none of them had ever been observed by our race; for only once every score of years would any scientist of Wu venture above ground, and even then he would emerge in some desert place where no human habitation existed.
But how did the millions of Wu and Zu manage to preserve life underground? How did they contrive to eat, breathe, and clothe themselves? That was one of the first questions I asked; and the answer came to me partly from Loa, and partly from my own observations.
The secret, as I had early surmised, was to be found in the prodigious scientific development of the Underworld. I do not exaggerate when I say that they were centuries in advance of our own race; they had evolved mechanical formulae and devices of which we have not the remotest conception. As an engineer by profession, I was naturally much interested in this phase of their growth; and while I was not able to study or understand all their numerous contrivances, yet I could understand enough to fill me with amazement and admiration. Every phase of the life of Wu, I found, depended upon science. Without it, they could not have existed for a single day; it was both astonishing and frightening to know how completely these people had come to rely upon their own inventions.
I shall not take time, at this point, to dwell upon all their elaborate appliances—which, indeed, would require a separate volume even for their enumeration. I shall leave out of account the intricate ventilating system, by which they pumped an adequate supply of air from the outer world; for I shall have occasion to refer to this again. Likewise, I shall not now describe their military engines, of which I have already given some idea, but which I was later to observe more intimately. I shall begin, therefore, by telling of the manufacture of food and clothing, which was conducted on principles I had never before considered possible.
Let me say, by way of explanation, that my food in the Professor's house had consisted entirely of queer-looking ingredients, comprised in part of purple capsules, such as I had been given in prison, and in part of a stringy, fibrous substance reminding me of seaweed. I was told, indeed, that the wealthier sections of the population occasionally enjoyed delicacies such as fish from subterranean rivers, and mushrooms grown in specially prepared cellars; but if Professor Tan Trum could afford such luxuries, he would not waste them on a barbarian such as myself.
My clothes, likewise, were of a substance I could not recognize—a woven substance a little like hemp and yet clearly not hemp, for it was not quite so coarse. But the fibres, on the other hand, did not resemble those of linen, cotton, silk, or wool. What could it be? The answer, as I learned from Loa, was that the native clothing, and likewise the food, was manufactured synthetically. From the most ordinary chemical ingredients—from oxygen and hydrogen as contained in water, from carbon as contained in carbon dioxide or in coal, from the nitrogen found in the air, and from the sulphur and phosphorus of the mines—they would create compounds resembling natural organic products.
The simplest of all to manufacture were starch and sugar, and a fibre like the cellulose of plants. For these, all that was required was a brilliant lamp, imitating the qualities of sunlight, a chemical cell which utilized the lamp-rays as the chlorophyll of the vegetable kingdom utilizes the solar beams, and an adequate supply of water and carbon. Thus the people might obtain all the carbohydrates they required for the table, and also all the fibres needed for weaving into paper and clothes; for, since cellulose constitutes the main ingredient of cotton and other vegetable fabrics, it was possible to produce a synthetic equivalent of the garments worn in the world above.