Soon after I left Mr. Edison’s employment a company was formed to develop my electric arc-light system. This system was adopted for street and factory lighting in 1886, but as yet I got no money — only a beautifully engraved stock certificate. Until April of the following year I had a hard financial struggle. Then a new company was formed, and provided me with a laboratory on Liberty Street, in New York City. Here I set to work to commercialize the inventions I had conceived in Europe.
After returning from Pittsburgh, where I spent a year assisting the Westinghouse Company in the design and manufacture of my motors, I resumed work in New York in a little laboratory on Grand Street, where I experienced one of the greatest moments of my life — the first demonstration of the wireless light.
I had been constructing with my assistants the first high-frequency alternators (dynamos), of the kind now used for generating power for wireless telegraphy. At three o’clock in the morning I came to the conclusion that I had overcome all the difficulties and that the machine would operate, and I sent my men to get something to eat. While they were gone I finished getting the machine ready, and arranged things so that there was nothing to be done, except to throw in a switch.
When my assistants returned I took a position in the middle of the laboratory, without any connection whatever between me and the machine to be tested. In each hand I held a long glass tube from which the air had been· exhausted. “If my theory is correct,” I said, “when the switch is thrown in these tubes will become swords of fire.” I ordered the room darkened and the switch thrown in — and instantly the glass tubes became brilliant swords of fire.
Under the influence of great exultation I waved them in circles round and round my head. My men were actually scared, so new and wonderful was the spectacle. They had not known of my wireless light theory, and for a moment they thought I was some kind of a magician or hypnotizer. But the wireless light was a reality, and with that experiment I achieved fame overnight.
Following this success, people of influence began to take an interest in me. I went into “society.” And I gave entertainments in return; some at home, some in my laboratory — expensive ones, too. For the one and only time in my life, I tried to roar a little bit like a lion.
But after two years of this, I said to myself, “What have I done in the past twentx-four months?” And the answer was, “Little or nothing.” I recognized that accomplishment requires isolation. I learned that the man who wants to achieve must give up many things — society, diversion, even rest — and must find his sole recreation and happiness in work. He will live largely with his conceptions and enterprises; they will be as real to him as worldly possessions and friends.
In recent years I have devoted myself to the problem of the wireless transmission of power. Power can be, and at no distant date will be, transmitted without wires, for all commercial uses, such as the lighting of homes and the driving of aeroplanes. I have discovered the essential principles, and it only remains to develop them commercially. When this is done, you will be able to go anywhere in the world — to the mountain top overlooking your farm, to the arctic, or to the desert — and set up a little equipment that will give you heat to cook with, and light to read by. This equipment will be carried in a satchel not as big as the ordinary suit case. In years to come wireless lights will be as common on the farms as ordinary electric lights are nowadays in our cities.
The matter of transmitting power by wireless is so well in hand that I can say I am ready now to transmit 100,000 horsepower by wireless without a loss of more than five percent in transmission. The plant required to transmit this amount will be much smaller than some of the wireless telegraph plants now existing, and will cost only $10,000,000, including water development and electrical apparatus. The effect will be the same whether the distance is one mile or ten thousand miles, and the power can be collected high in the air, underground, or on the ground.
“Making Your Imagination Work for You.” By M. K. Wisehart. The American Magazine, April 1921.
“The first result was one of the experiments which I at that time showed in a public lecture, motive devices operated by merely connecting them to one terminal of a source of oscillations–a high frequency coil.
I have often been told that my most important results in invention was the demonstration of the practicability of transmitting energy over one wire; because, once we can transmit energy over one wire we can use also the Earth, for the Earth is equivalent to a large conductor- a better conductor than copper wire.
This was one of the results I got, but the most striking one I will show you now.
"This second result shows how energy goes through space without any wire. That was a most striking experiment which was repeated all the world over and was published in thousands and thousands of papers. There is a field produced–of high frequency–and in this field I hold two tubes of glass in my hands. These glass tubes spring into powerful light. That was an experiment which carried the whole world by storm; but to me it was the first evidence that I was conveying energy to a distance, and it was a tremendous spur to my imagination and to my energy to develop what I had started.”
(Tesla explaining his wireless art in a pre-hearing interview with his legal counsel in 1916 to protect his radio patents from the Guglielmo Marconi and the Marconi Company.)
“Nikola Tesla On His Works With Alternating Currents and Their Application to Wireless Telegraphy, and Transmission of Power.” Twenty First Century Books, Breckenridge, Colorado, 2002.
“Looking at all this busy world about us, on all this complex mass as it daily throbs and moves, what is it but an immense clock-work driven by a spring? In the morning, when we rise, we cannot fail to note that all the objects about us are manufactured by machinery: the water we use is lifted by steam-power; the trains bring our breakfast from distant localities; the elevators in our dwelling and our office building, the cars that carry us there, are all driven by power; in all our daily errands, and in our very life-pursuit, we depend upon it; all the objects we see tell us of it; and when we return to our machine-made dwelling at night, lest we should forget it, all the material comforts of our home, our cheering stove and lamp, remind us of how much we depend on power. And when there is an accidental stoppage of the machinery, when the city is snowbound, or the life sustaining movement otherwise temporarily arrested, we are affrighted to realize how impossible it would be for us to live the life we live without motive power. Motive power means work. To increase the force accelerating human movement means, therefore, to perform more work.”
“The Problem of Increasing Human Energy.”Century Illustrated Magazine, June, 1900.
“To the popular mind this sensational advance conveys the impression of a single invention but in reality it is an art, the successful practice of which involves the employment of a great many discoveries and improvements. I viewed it as such when I undertook to solve wireless problems and it is due to this fact that my insight into its underlying principles was clear from their very inception.
“In the course of development of my induction motors it became desirable to operate them at high speeds and for this purpose I constructed alternators of relatively high frequencies. The striking behavior of the currents soon captivated my attention and in 1889 I started a systematic investigation of their properties and the possibilities of practical application. The first gratifying result of my efforts in this direction was the transmission of electrical energy throughone wire without return, of which I gave demonstrations in my lectures and addresses before several scientific bodies here and abroad in 1891 and 1892. During that period, while working with my oscillation transformers and dynamos of frequencies up to 200,000 cycles per second, the idea gradually took hold of me that the earth might be used in place of the wire, thus dispensing with artificial conductors altogether. The immensity of the globe seemed an unsurmountable obstacle but after a prolonged study of the subject I became satisfied that the undertaking was rational, and in my lectures before the Franklin Institute and National Electric Light Association early in 1893 I gave the outline of the system I had conceived. In the latter part of that year, at the Chicago World’s Fair, I had the good fortune of meeting Prof. Helmholtz to whom I explained my plan, illustrating it with experiments. On that occasion I asked the celebrated physicist for an expression of opinion on the feasibility of the scheme. He stated unhesitatingly that it was practicable, provided I could perfect apparatus capable of putting it into effect but this, he anticipated, would be extremely difficult to accomplish.
Figs. 5 & 6. — A Section of the Earth and Its Atmospheric Envelope Drawn to Scale. It is Obvious That the Hertzian Rays Cannot Traverse So Thin a Crack Between Two Conducting Surfaces For Any Considerable Distance. Without Being Absorbed, Says Dr. Tesla, in Discussing the Ether Space Wave Theory.
"I resumed the work very much encouraged and from that date to 1896 advanced slowly but steadily, making a number of improvements the chief of which was my system of concatenated tuned circuits and method of regulation, now universally adopted. In the summer of 1897 Lord Kelvin happened to pass through New York and honored me by a visit to my laboratory where I entertained him with demonstrations in support of my wireless theory. He was fairly carried away with what he saw but, nevertheless, condemned my project in emphatic terms, qualifying it as something impossible, “an illusion and a snare.” I had expected his approval and was pained and surprised. But the next day he returned and gave me a better opportunity for explanation of the advances I had made and of the true principles underlying the system I had evolved. Suddenly he remarked with evident astonishment: “Then you are not making use of Hertz waves?” “Certainly not,” I replied, “these are radiations. No energy could be economically transmitted to a distance by any such agency. In my system the process is one of true conduction which, theoretically, can be effected at the greatest distance without appreciable loss.” I can never forget the magic change that came over the illustrious philosopher the moment he freed himself from that erroneous impression. The skeptic who would not believe was suddenly transformed into the warmest of supporters. He parted from me not only thoroughly convinced of the scientific soundness of the idea but strongly exprest his confidence in its success. In my exposition to him I resorted to the following mechanical analogues of my own and the Hertz wave system.
"Imagine the earth to be a bag of rubber filled with water, a small quantity of which is periodically forced in and out of the same by means of a reciprocating pump, as illustrated. If the strokes of the latter are effected in intervals of more than one hour and forty-eight minutes, sufficient for the transmission of the impulse through the whole mass, the entire bag will expand and contract and corresponding movements will be imparted to pressure gauges or movable pistons with the same intensity, irrespective of distance. By working the pump faster, shorter waves will be produced which, on reaching the opposite end of the bag, may be reflected and give rise to stationary nodes and loops, but in any case, the fluid being incompressible, its inclosure perfectly elastic, and the frequency of oscillations not very high, the energy will be economically transmitted and very little power consumed so long as no work is done in the receivers. This is a crude but correct representation of my wireless system in which, however, I resort to various refinements. Thus, for instance, the pump is made part of a resonant system of great inertia, enormously magnifying the force of the imprest impulses. The receiving devices are similarly conditioned and in this manner the amount of energy collected in them vastly increased.
Fig. 7. — The Theory Has Been Seriously Advanced and Taught that the Radio Ether Wave Oscillations Pass Around the Earth by Successive Reflections, as Here Shown. The Efficiency of Such a Reflector Cannot be more than 25 Per Cent; the Amount of Energy Recoverable is a 12,000-mile Transmission being but One Hundred and Fifteen Billionth Part of One Watt, with 1.000 Kilowatts at the Transmitter.
"The Hertz wave system is in many respects the very opposite of this. To explain it by analogy, the piston of the pump is assumed to vibrate to and fro at a terrific rate and the orifice thru which the fluid passes in and out of the cylinder is reduced to a small hole. There is scarcely any movement of the fluid and almost the whole work performed results in the production of radiant heat, of which an infinitesimal part is recovered in a remote locality. However incredible, it is true that the minds of some of the ablest experts have been from the beginning, and still are, obsest by this monstrous idea, and so it comes that the true wireless art, to which I laid the foundation in 1893, has been retarded in its development for twenty years. This is the reason why the “statics” have proved unconquerable, why the wireless shares are of little value and why the Government has been compelled to interfere.
"We are living on a planet of well-nigh inconceivable dimensions, surrounded by a layer of insulating air above which is a rarefied and conducting atmosphere (Fig. 5). This is providential, for if all the air were conducting the transmission of electrical energy thru the natural media would be impossible. My early experiments have shown that currents of high frequency and great tension readily pass thru an atmosphere but moderately rarefied, so that the insulating stratum is reduced to a small thickness as will be evident by inspection of Fig. 6, in which a part of the earth and its gaseous envelope is shown to scale. If the radius of the sphere is 12½”, then the non-conducting layer is only 1/64″ thick and it will be obvious that the Hertzian rays cannot traverse so thin a crack between two conducting surfaces for any considerable distance, without being absorbed. The theory has been seriously advanced that these radiations pass around the globe by successive reflections, but to show the absurdity of this suggestion reference is made to Fig. 7 in which this process is diagrammatically indicated. Assuming that there is no refraction, the rays, as shown on the right, would travel along the sides of a polygon drawn around the solid, and inscribed into the conducting gaseous boundary in which case the length of the side would be about 400 miles. As one-half the circumference of the earth is approximately 12,000 miles long there will be, roughly, thirty deviations. The efficiency of such a reflector cannot be more than 25 per cent, so that if none of the energy of the transmitter were lost in other ways, the part recovered would be measured by the fraction (¼)30. Let the transmitter radiate Hertz waves at the rate of 1,000 kilowatts. Then about one hundred and fifteen billionth part of one watt is all that would be collected in a perfect receiver. In truth, the reflections would be much more numerous as shown on the left of the figure, and owing to this and other reasons, on which it is unnecessary to dwell, the amount recovered would be a vanishing quantity.
Fig. 8. — This Diagram Illustrates How, During a Solar Eclipse, the Moon’s Shadow Passes Over the Earth With Changing Velocity, and Should Be Studied In Connection With Fig. 9. The Shadow Moves Downward With Infinite Velocity at First. Then With Its True Velocity Thru Space, and Finally With Infinite Velocity Again.
"Consider now the process taking place in the transmission by the instrumentalities and methods of my invention. For this purpose attention is called to Fig. 8, which gives an idea of the mode of propagation of the current waves and is largely self-explanatory. The drawing represents a solar eclipse with the shadow of the moon just touching the surface of the earth at a point where the transmitter is located. As the shadow moves downward it will spread over the earth’s surface, first with infinite and then gradually diminishing velocity until at a distance of about 6,000 miles it will attain its true speed in space. From there on it will proceed with increasing velocity, reaching infinite value at the opposite point of the globe. It hardly need be stated that this is merely an illustration and not an accurate representation in the astronomical sense.
Fig. 9. — Theory.
"The exact law will be readily understood by reference to Fig. 9, in which a transmitting circuit is shown connected to earth and to an antenna. The transmitter being in action, two effects are produced: Hertz waves pass through the air, and a current traverses the earth. The former propagate with the speed of light and their energy is unrecoverable in the circuit. The latter proceeds with the speed varying as the cosecant of the angle which a radius drawn from any point under consideration forms with the axis of symmetry of the waves. At the origin the speed is infinite but gradually diminishes until a quadrant is traversed, when the velocity is that of light. From there on it again increases, becoming infinite at the antipole. Theoretically the energy of this current is recoverable in its entirety, in properly attuned receivers.
Fig. 10. — Tesla’s World-Wide Wireless Transmission of Electrical Signals, As Well As Light and Power, Is Here Illustrated in Theory, Analogy and Realization. Tesla’s Experiments With 100 Foot Discharges At Potentials of Millions of Volts Have Demonstrated That the Hertz Warn Are Infinitesimal In Effect and Unrecoverable: the Recoverable Ground Waves of Tesla Fly "Through the Earth”. Radio Engineers Are Gradually Beginning to See the Light and That the Laws of Propagation Laid Down by Tesla Over a Quarter of a Century Ago Form the Real and True Basis of All Wireless Transmission To-Day.
“Some experts, whom I have credited with better knowledge, have for years contended that my proposals to transmit power without wires are sheer nonsense but I note that they are growing more cautious every day. The latest objection to my system is found in the cheapness of gasoline. These men labor under the impression that the energy flows in all directions and that, therefore, only a minute amount can be recovered in any individual receiver. But this is far from being so. The power is conveyed in only one direction, from the transmitter to the receiver, and none of it is lost elsewhere. It is perfectly practicable to recover at any point of the globe energy enough for driving an airplane, or a pleasure boat or for lighting a dwelling. I am especially sanguine in regard to the lighting of isolated places and believe that a more economical and convenient method can hardly be devised. The future will show whether my foresight is as accurate now as it has proved heretofore.”
“When wireless is perfectly applied the whole earth will be converted into a huge brain, which in fact it is, all things being particles of a real and rhythmic whole. We shall be able to communicate with one another instantly, irrespective of distance. Not only this, but through television and telephony we shall see and hear one another as perfectly as though we were face to face, despite intervening distances of thousands of miles; and the instruments through which we shall be able to do his will be amazingly simple compared with our present telephone. A man will be able to carry one in his vest pocket.”
“More than 25 years ago I began my efforts to harness the cosmic rays and I can now state that I have succeeded in operating a motive device by means of them.
"I will tell you in the most general way. The cosmic ray ionizes the air, setting free many charges—ions and electrons. These charges are captured in a condenser which is made to discharge through the circuit of the motor.
I have hopes of building my motor on a large scale, but circumstances have not been favorable to carrying out my plan.
I do not use the plan involving the conductivity of the upper strata of the air, but I use the conductivity of the earth itself, and in this I need no wires to send electrical energy to any part of the globe.”
“Tesla’s Cosmic Motor May Transmit Power Round Earth.” Brooklyn Eagle July 10, 1932.