Chapter XII: The National Research Council 349 (13)

The _eternal truth_ was, according to my understanding at that
time, the sacred background of Tyndall’s scientific faith, and
the works of the great scientific discoverers, their lives, and
their methods of inquiry into physical phenomena were the only
sources from which the human mind can draw the light which will
illuminate that sacred background. He nourished that faith with a
religious devotion, and his appeals in the name of that faith were
irresistible. His friends in America and in England, who were glad
to have him as their advocate of the cause of scientific research,
had the same faith that he had, and they nourished it with the
same devotion. I know to-day ... that this faith was kindled and
kept alive ... by the light of the life and of the wonderful
discoveries of Michael Faraday.... He was their contemporary, and
his achievements, like a great search-light, showed them the true
path of scientific progress.

The worship of the eternal truth and the burning desire to seek an ever-broadening revelation of it constitute the mental attitude which I call “idealism in science.” Its growth in the British Empire, and particularly at the University of Cambridge, has been most remarkable since the great movement started under the leadership of Maxwell a little over fifty years ago. What progress have we made since Tyndall’s visit to this country in 1872? If in my narrative I succeed in answering this question I shall be more than satisfied, and I shall certainly send a translation of it in part to my scientific friends in Belgrade. It will tell them what I ought to have told them four years ago.

* * * * *

I return now to the point in my story where I digressed. The 14th of April, 1896, is recorded in my calendar as a happy day. The 15th started with a balmy spring morning full of glorious sunshine. The suggestion to walk through Central Park to Columbia College to my morning lecture could not be resisted, and I reached the lecture-room full of the joy of life which fills the heart of every healthy youth. My students told me later that the first part of my lecture that morning displayed that joy. But, near the end of the lecture, I suddenly collapsed. A sudden chill struck me like a bolt from a clear sky. Five days later my life hung in the balance; there was a desperate struggle between a stout heart and the busy poisons of dreaded pneumonia. The heart won out. But when the crisis had passed, and my physician thought that I was sufficiently strong to stand the shock of terrible news, he told me that my wife had died several days before, a victim of dreaded pneumonia. She had caught the seed of this merciless disease while nursing me. My weakened heart stood the shock, but every one of my nerves seemed to snap in two. For the first time in my life I recognized the full meaning of will-power; I recognized it because I knew that the spiritual motor, the power of which I had always felt, was there no longer. For the first time since leaving my native Idvor, twenty-six years before, I had to be steered and looked after by others. Life never looked so hopeless as it did during that awful spring of 1896. But I wanted to live, because I had a little daughter to bring up. That, in fact, was the only thing that I wanted to live for; everything else seemed either devoid of interest, or much beyond my reach. It is an awful thing to lose one’s self-reliance. Aims and aspirations appeared to me like little toy balloons that children play with; our nerves, I thought, are the strings which keep them afloat within the reach of our vision. When these strings snap in two, our aims and aspirations, like toy balloons, disappear rapidly into thin air.

My physician recommended that during that summer I should settle down in Norfolk, Connecticut, to give the bracing climate of this New England town in the Berkshire hills a chance to rebuild what overwork, under nervous tension, and pneumonia had undermined and torn down. A New York physician, who knew me through my X-ray work, offered to rent me his summer residence, facing Haystack Mountain, the highest peak in Norfolk, and I accepted it. This mountain is really only a hill, hardly one thousand feet higher than the road at its foot, but as I sat on the piazza in front of that little cottage and looked at the so-called observatory, a square frame structure on the top of this hill, from which people caught the distant view of the Housatonic valley, I wondered whether I should ever be strong enough to climb to its top. I recalled my exploits in Switzerland, thirteen years before, and, utterly discouraged by the comparison, I accepted with calm resignation that I had grown old and decrepit in less time than it takes other people to become middle-aged. Whenever I thought of my past, present, or future, I always managed to draw some gloomy conclusion of that kind, and, so far as my cloudy fancy could see, I felt that I had finished my career in dismal failure. People told me that these were queer notions due to mental depression, from which I would soon recover. But, as time went on and there was no relief, I resented it when people tried to console me with, what I considered, empty promises of a brighter future. There suddenly appeared an angel who promised nothing but gave much.

Another New York physician, the well-known Doctor Frederick Shepard Dennis, also an admirer of my X-ray work, had a summer residence at Norfolk. He was practically a native of this quaint New England town, and believed in its great virtues as a resort for convalescents. He was very anxious that my summer vacation there should put me on my feet again, but he saw that my introspective life on the lonely piazza facing Haystack Mountain blocked every road which might lead to my physical and mental restoration. “Professor,” said he one day to me, “if you do not stop thinking about yourself you will never get well.” “But,” said I, “what else is there to think about? I hate to think about that horrible green phosphorescence of vacuum tubes, about the X-rays, fluorescent screens, and skeletons of hands and feet and ribs. Those are the things which haunted incessantly my burning brain during the pneumonia fever, and I shall never think of them again if I can help it. I should like to think about some other problems which are waiting in my laboratory, but what is the use? I have no hope of living long enough to solve them, or that, if I live, I shall have the necessary brain energy to work out their solution. Besides, whenever I begin to think of something pleasant or interesting my heart suddenly gives a violent thump, and sends a cold shiver through my timid veins. I must think of myself, because I am always on my guard against something that might happen at any moment to cut the last thread of my shaky vitality. It is this everlasting fear that keeps me thinking about myself.” The good doctor looked thoughtful, but said nothing; a few days later he drove up in a little yellow runabout, drawn by a pair of cobs of beautiful dark chestnut color, which were a splendid product of his stud farm; they shone like old mahogany. “How do you like them, professor?” asked the doctor, as he scrutinized my admiring gaze. “They are a thing of beauty and a joy forever,” said I, and I meant what I said. The next day the cobs, with wagon and harness, were mine; they were only three years old, and, although broken to harness, they were quite raw and needed training. I got them after pledging my word to the doctor that I would train them. My native Banat is like Kentucky. Everybody raises horses, and everybody knows by intuition how to handle a horse. I was told by experts that I handled those cobs just right. While training them I really trained my own nerves. They needed it more than the cobs did. “Horse sense” has meant to me ever since a sense which enables man to train a horse, and that means to give up your whole heart and soul to the horse. The trainer must never think of himself, but always of his beloved animal. He must be patient and persistent, kind and affectionate, forgiving mistakes and showing full appreciation for even the smallest honest effort. Only by the exercise of these virtues can he succeed in developing in the horse the habit of being a splendid horse. Doctor Dennis was a great lover of horses, and he knew all that, and thought, as he told me later, that it was the best medicine for me.

My cobs acquired the best of habits, and at the end of a year they were two beautifully balanced animals, carrying their proud heads on high, and stepping up in perfect unison. They seemed, when in full action, to be anxious to strike their foreheads with their knees. To sit behind those animals, and watch their swaggering motion around the horse-show ring, gave a thrill never to be forgotten. The New York horse-show in Madison Square Garden, in the autumn of 1897, and the Philadelphia horse-show at Wissahickon, in the spring of 1898, established the great reputation of Comet and Princess Rose, the cobs that I had been training during eighteen months. They won many prizes, but none of them was as welcome as the prize of my restored health. I got well without knowing that I was getting well; the only improvement that I was watching and thinking about was the improvement of my beautiful cobs, but, nevertheless, my laboratory assistant Cushman noticed in the early spring of 1897 that I had already begun to speak much more encouragingly about some of my old laboratory problems; he noticed it, and he was happy again. The X-ray problems were not among them; I never recovered from the feeling of horror which the thought of them gave me during my sickness in April, 1896.

Reginald Rives, one of the social leaders of New York, was the judge at Wissahickon who awarded the prizes to my cobs. We had been in college together, but when he saw me at the horse-show he did not recognize me at first, because, as he informed me later, he did not expect to see a college professor driving high-steppers at a horse-show. He spoke very highly of my cobs, which won from a competitor like millionaire Widener’s stable in Philadelphia.

“Pupin,” exclaimed Rives, “if you can handle your students as well as you can handle your cobs, you are the greatest professor in America.” “I could,” said I, “if I had to handle only two students at a time, but not two hundred.” Rives repeated this remark to his brother, a trustee of Columbia University, and the trustee saw in it quite a chunk of educational philosophy. The preceptorial system at Princeton reminds one of this philosophy. Will the American colleges ever adopt it?

A famous Boston lover of horses, a Mr. Jordan, saw my cobs at the Wissahickon horse-show and made me a handsome bid for them in cash besides “throwing in” a very handsome Irish hunter which had won a prize in the jumping class. The hunter became my saddle-horse, and served me loyally for fully twelve years. No better saddle-horse ever cantered over the hillsides of Litchfield County than Clipper, the Irish hunter, my trusty friend and companion, particularly during my summer vacations. Thanks to Comet and Princess Rose, and to good old Clipper, and to the bracing climate of Norfolk hills, the joy of life returned again.

My first job after landing at Castle Garden was on a farm, and there I had vowed that as soon as I could afford it I would buy myself a real American farm. A little over twenty years later, in 1897, I bought a farm at Norfolk; this blessed spot, where I regained my health and happiness, became my real American home, and I have never had a desire to seek a better haven of happiness in any other place, either here or in Europe.

The native of Norfolk is a typical Connecticut Yankee. Neither the wealth nor the social position of a new summer visitor can faze him. His dignity and self-respect forbid him to kowtow to any city swell. You will get his respectful attention if you deserve it; but you must earn it by your acts at Norfolk. You cannot command it by the power of anything you bring with you from the city to your summer vacation. While you are in Norfolk in summer, you are a summer boarder, an outsider, with traditions back of you which no native of Norfolk knows anything about. The force of all this was once so strongly impressed upon me that I never forgot it.

Norfolk, like every New England town, has its annual town meetings, when the accounts of the town for the closing current year are carefully analyzed, appropriations are made for the coming year, and the selectmen and other administrative officers are elected. After I had become a landowner in Norfolk, I attended these town meetings regularly, and took part in their discussions, and there for the first time I became acquainted, by personal contact, with the fundamental elements of Anglo-Saxon civilization. At one of those town meetings I urged the improvement of the public highways, using the argument that better roads would attract more summer residents from the great cities and, I was certain, would advance the prosperity of the town. My arguments were received with respectful silence, and no sooner had I finished my speech than a Mr. Nettleton, the oldest voter in the township, got up and, turning his black goggles toward me, addressed me somewhat as follows:

“Our roads are just as good as they ever were; our ancestors taught us how to take care of them, and they are good enough for us. You say that if we improve them we would get more summer visitors, who, with their wealth, would increase the prosperity of our town. We don’t care for that kind of prosperity; it brings vanity and false pride into our New England homes, which you city people carry around with you.” Then, pointing his trembling finger at me, the old man exclaimed: “You, particularly, are guilty of this offense; you were the first who showed our simple people here how to swagger about this town on a horse with a rabbit tail.”

He referred to the almost universal custom at that time of docking a horse’s tail; the tails of my famous cobs as well as of my saddle-horse Clipper had been docked. After this speech, I suspended my propaganda for more up-to-date roads. Two years later, another incident occurred which is worth relating here. Mr. Carter, a Norfolk hunter of much local fame, had a fine pointer dog. He went to Europe one summer and left his dog in charge of a friend. But the dog ran away, and chased through all the woods of Norfolk, looking for his master. One day he came to my house; he was hungry, thirsty, tired out, and perfectly unhappy, having failed to find his master. I petted him, gave him fresh water to drink and some food to eat, and, while he was feasting, spoke to him and paid him many compliments on account of his affectionate attachment to his master. After his hearty meal he fell asleep near my feet on the piazza, and when he woke up he looked at me and seemed to be a much happier dog. From that moment on he followed me everywhere, running after my horse when I went out riding. One day I was cantering slowly along the road passing old Nettleton’s house. I saw the old man standing near the road, apparently waiting for somebody. When I was quite near him he beckoned me to stop, which I did, and he addressed me:

“Professor, I was very severe with you two years ago at that town meeting. But I did not know you; now I do. That dog there would not stay with anybody in this town, but he stays with you, and he follows you just as he followed his master. You are good to him, and the dog knows it. I have great confidence in a dog’s judgment, and I know now that you are a good man, just as good as any of the folks in this here New England town.” Then, stretching out his bony hand to me, he said: “Shake, forgive and forget, and let us be good friends. I shall never oppose you again at our annual town meetings. What’s good for you is good enough for me and for our little town.”

No offer of friendship was ever more welcome to me, and there never was a friendship of which I was more proud. Before many days had passed, the natives of Norfolk, from the illustrious Eldridge family, the angels of the town, down to the most humble day-laborer, felt the same toward me as old Nettleton did; that is, I always thought so, and I have never had any reason to think otherwise. No resolution moved by me at the annual town meetings ever failed to pass, but I always moved slowly, and not until I was quite sure that the motion was in the right direction. I would sooner have risked losing the good opinion of the trustees of Columbia University than that of the good people of Norfolk, my American Idvor. During my summer vacations in Norfolk, I have always felt just as much at home, and as happy and contented, as I did in my native Idvor when, during my student days in Europe, I spent my summer vacations there. Whenever I returned to my laboratory from my summer vacation in the bracing atmosphere of Norfolk, I have always felt that no problem there could resist the force of my stored-up nervous energy. That feeling early encouraged me in the belief that I had completely recovered from the breakdown of the spring of 1896, and this belief gave wings to every new effort.

When the news of the discovery of the Roentgen rays reached me in December of 1895, I was busy with the research of a problem which I had taken up in 1894, while making a foot tour in Switzerland. This is the problem which I took up again after the recovery from the breakdown of 1896. I must confess here that I never returned to X-ray research, because for a long time after my illness even the sight of an X-ray tube made me almost hysterical.

During the first half of the summer of 1894, Mrs. Pupin and I were staying at a little hotel on Lake Wannensee in Switzerland; I was preparing my lectures on the mathematical theory of sound. Lord Rayleigh’s treatise called my attention to the classical problem which ten years before I first saw in La Grange’s famous treatise. I had bought it second-hand in Paris, and had studied it in my mother’s garden at Idvor. The problem was a hypothetical one relating to an imaginary and not to a real physical case. It may be stated as follows:

A string without weight is stretched like a violin string between two fixed points; at equidistant intervals along this string are attached equal weights, say bird-shot. The problem is, how will this string, loaded with weights, vibrate when disturbed by an impulse? La Grange found a beautiful solution for this historic problem, and the solution marks the beginning of an epoch in the history of mathematical physics. This solution enabled him to analyze mathematically the vibrations of a violin string, one of the famous mathematical problems of the eighteenth century. I made a bold attempt to find a solution for a more general and less hypothetical form of this problem. I supposed that the string itself had weight, and that it, as well as the little weights attached to it, moved through a viscous medium. I felt intuitively what the solution should be, and considered it of much scientific importance. I finally found the most general mathematical solution of this generalized problem, and the beauty of it was that it could be stated in a very simple language. I shall state it later. The solution was exactly what I had expected it to be, and it thrilled me more than any work that I had ever done. I always believed that my training in ground-signalling which the herdsman of Idvor had taught me some twenty years before was responsible for this intuitive guess. Early impressions, particularly those relating to novel scientific facts, are very intense.

I was much encouraged by the thought that I was able to add very substantially to the solution of a historic problem first solved by famous La Grange. In order to communicate some of my joy to Mrs. Pupin, I told her that I was ready to give up mathematical reading for the rest of that summer, and we started on a drive through Switzerland. That is, she drove, while I walked a good part of the time, particularly when the carriage was moving along the zigzag roads going up to a pass, which happens often in Switzerland drives. Making short cuts, I met her every now and then on the up-grade parts of the steep and winding roads, and rode with her on the down-grade. During these walks, being alone, I pondered a great deal about my solution of the generalized La Grangian problem. One day, while climbing up to the Furka pass, it occurred to me that since the motion of electricity through a wire experiences reacting forces similar to those in the motion of the material elements in a stretched string, my generalized solution should be applicable to the motion of electricity, and I was immediately aware that I had made a very important invention. I tried to convince Mrs. Pupin of it, but she said: “I will believe what you say and will gladly congratulate you if you will promise that you will not be absent-minded during the rest of our trip.” I promised, but it was very difficult to live up to the promise. I never told her how often I longed to be back in my modest laboratory in the musty cellar under President Low’s office at Columbia College, and that too in spite of the heavenly beauty of the views which on my walks met me on every turn of the winding roads which lead up to the wonderful passes of Switzerland. I was most anxious to submit my theory to an experimental test. When our tour in Switzerland was finished I had every detail of the proposed experimental tests worked out in my head, and yet my good wife never accused me of being absent-minded. In less than a year from that time I had finished my first rough test, and was preparing for a more elaborate investigation when the discovery of the X-ray was announced, at the very end of 1895, and I, like everybody else, dropped everything and eagerly sought information about this wonderful discovery. It was the work I dropped then which I took up again after my recovery from the breakdown of 1896.

Now what is the invention which occurred to me first on my walk to the Furka pass in Switzerland in the summer of 1894? A bit of scientific history is connected with it, which I shall tell here briefly:

A vibrating motion of electricity at one end of a long wire is propagated along the wire in much the same way as the vibratory motion of a rope or string is propagated from one of its terminals to the other. This propagation of electrical motion from one end of a long conducting wire to the other was first investigated by Professor William Thomson, the late Lord Kelvin, of the University of Glasgow, in 1855, when the first Atlantic cable was projected. He worked out the problem for electrical signalling over a submarine cable, and three years later Kirchhoff, who was one of my teachers in Berlin, worked it out for telegraphic signalling over land-lines stretched over poles. When telephony was invented in 1876, there was, of course, a demand for a mathematical theory of telephonic transmission over long conducting wires. He who understood Thomson’s and Kirchhoff’s work could experience no serious difficulty in working it out. Vaschy, a Frenchman, and Heaviside, an Englishman, were the first to work it out; they did it in the chronological order just indicated, Vaschy leading Heaviside by about two years. They both observed that just as in cable and land-line telegraphy so also in telephony the reduction of the transmitted electrical force was the smaller the larger the so-called inductance of the transmitting wire. Many people believe that this observation was an important discovery; I never thought so, because I believed that Thomson’s and Kirchhoff’s work made that observation obvious. But, however that may be, the observation was made by Vaschy two years before it was made by Heaviside, and neither one nor the other saw in it a special case of a general physical principle, which the Allies appreciated much during the World War in their struggles against the submarines. I shall describe it briefly:

Sound is transmitted through water or through a solid much more efficiently than it is through air. I knew that, when, as herdsman’s assistant in Idvor, I learned the art of signalling through the ground. Now why should water or hard and heavy ground transmit sound better than air does? Idvor’s herdsman did not tell me that, but, having gained the knowledge of the fact very early, I was prepared to seize upon the dynamical explanation as soon as I needed it; and I felt the need of it in Switzerland in the summer of 1894.

Transmission of sound means transmission of vibratory motion from one element of a substance to the contiguous elements. The element which transmits its vibratory energy acts and the elements which receive it react. Each element is capable of exerting three reacting forces. One is against the change of velocity of its motion, that is, against change of momentum. This reaction is called the kinetic reaction, and, as I have pointed out before, it was discovered by Galileo three hundred years ago. The second reaction is against the elastic compression of the receiving element. It is called the elastic reaction, and was discovered by Hook, a contemporary of Newton, two hundred years ago. The third is a frictional reaction, the knowledge of which is very old. There are, therefore, three forms of energy generated in the reacting element of every vibrating body by the work of the acting element. The first reaction results in energy of motion of the mass of the reacting element; the second one results in the energy of its elastic compression; and the third one generates heat. The first and the second are energies of sound vibration and are transmitted again to the contiguous elements, but the third is not a vibratory sound energy and is not transmitted as such; it remains as heat and represents the reduction of sound energy transmitted from any one part to the contiguous parts. It is obvious that this reduction will be, relatively, the smaller the greater the first two reactions are in comparison with the frictional reaction. Heavy, incompressible bodies, like water, metals, or hard solid ground, have incomparably greater kinetic and elastic reactions than air, hence they transmit sound much better than air does. This physical principle did splendid service during the World War in submarine and subterranean detection by sound. The herdsman’s assistants in Idvor, when I was a boy, profited much from it in their signalling through the ground. I am not aware that Vaschy and Heaviside had a clear knowledge of it. If I am correct, then it is quite remarkable that Serb peasants should have been cognizant of a physical principle which was probably unknown to English and French savants, like Vaschy and Heaviside.

Passing now by analogy from motion of matter to motion of electricity, we can, speaking figuratively, state that vibratory motion of electricity will be transmitted from one end of a conducting wire to the other the more efficiently the heavier and the less compressible that electricity is, or, dropping now our figurative mode of speech, we can say that, other things being equal, the higher the kinetic and the elastic reaction of the moving electricity the more efficiently will the energy of its vibratory motion be transmitted over the wire. But that means that the inductance of the wire should be made as large and its capacity as small as possible. That much was perfectly obvious in Thomson’s and Kirchhoff’s work, some twenty years before Vaschy and Heaviside took up the mathematical theory of telephonic transmission. These two celebrated mathematicians, however, deserve much credit for their enthusiastic backing of inductance among the sceptical telephone engineers, who, at that time, knew little of the mathematical theory and of the general principle of transmission of vibratory motions.

A coil of wire wound around an iron core is the first picture in our mind when we hear inductance mentioned. Hence, if inductance increases the efficiency of transmission in a telephone transmission-line, and you cannot introduce it into the line in large amounts in any other way, then one would certainly suggest putting a lot of coils into the telephone-line and examining the results of this haphazard guess. Vaschy tried this guess, and failed. The late Mr. Pickernell, chief engineer of the long-distance department of the American Telephone and Telegraph Company, also tried it, and he also failed. It was obvious that, as Heaviside expressed it, experiment gave no encouragement with regard to inductance introduced in this way. I tried it and found that experiment offered very much encouragement to inductance introduced this way; I succeeded, because I did not guess; I was guided by the mathematical solution of the generalized La Grangian problem. What does this solution say when applied to electrical motions in a wire? It says this: Place your inductance coils into your telephone-line at such distances apart that for all vibratory motions of electricity which it is desirable to transmit there shall be several coils per wave-length. In telephonic transmission of speech that means one coil every four or five miles on overhead wires, and one coil in about every one to two miles in a telephone cable. For these wave-lengths, the wire possessing discreet lumps of inductance in the form of inductance-coils acts like a wire with uniformly distributed inductance. Such a wire transmits efficiently according to the general physical principle described above. In order to illustrate this by a mechanical analogy, we can say that a light silk cord stretched between two fixed points and carrying at equidistant points heavy bird-shot will act like a heavy uniform cord for all vibratory motions the wave-length of which embraces several intervals separating the bird-shot, and will transmit these motions much more efficiently from one end of the cord to the other than if the bird-shot were not there. This simple experiment with bird-shot and a long stretched cord can easily be tried; it is a very inexpensive experiment and will convince you even if you know nothing about the mathematical elements of the problem. This is the simple experiment which I had in my head during my tramping along the zigzag roads in Switzerland in 1894. A professor of physics, who often acted as consulting physicist to telephone companies, had such a loaded cord hung up over his lecture-room table for the purpose of explaining transmission of wave-motion from one end of the cord to the other, but he never inferred anything from it regarding loading a telephone-line with inductance-coils. When I called his attention to it, and joked about it, he blamed his hard luck, implying, I thought, that solving a dynamical problem and building upon the foundation of this solution an electrical invention is a question of luck.

From the simple apparatus, just referred to, to the elaborate electrical demonstrations which would convince stubborn and hard-headed telephone engineers, was a very long pull. The most embarrassing feature in these demonstrations was that I could not afford large expenditures of money to carry them out on actual telephone conductors; besides, it would have been unwise to disclose to interested parties, the owners of long-distance telephone-lines, a theory for which I had not yet obtained a satisfactory experimental proof. I had to invent laboratory apparatus equivalent to telephone lines or cables of great length, which would enable me to do all the experimenting in my laboratory. That required almost as much thought, inventive effort, and mathematical achievement as the solution of the extended La Grangian problem.

The first part of my research I communicated to the American Institute of Electrical Engineers in March, 1899. It dealt only with the mathematical theory of my laboratory apparatus. It spoke a great deal about La Grange, but nothing directly about the invention. In October of that year, a friend of mine, Doctor Cary T. Hutchinson, told me that he suspected that an invention was hidden in that communication. “If you have detected it, others have detected it also, and are by this time in the Patent Office,” said I. “Are you not there yourself?” asked Hutchinson, looking somewhat disturbed, and when he heard that I was not he looked discouraged. When, however, I declared my readiness to undertake to design for some clients of his a telephone cable to operate between New York and Boston, guaranteeing to employ a wire not bigger than in ordinary cables capable of operating satisfactorily over a distance of only twenty miles, Hutchinson grew quite serious, and advised me to apply for a patent before doing anything else. I finally followed his advice, and not any too soon. There were others, besides Hutchinson, who had recognized that in my communication to the American Institute of Electrical Engineers there was hidden an invention for which telephone engineers had been eagerly waiting ever since the birth of the telephone art. This created an interference in the Patent Office which annoyed me, but not nearly so much as I had been annoyed there before. About a year from the date of my application for patent, the American Telephone and Telegraph Company acquired my American patent rights, treating me most generously. It gave me what I asked; my friends thought that I had not asked enough, but to a native of Idvor a dollar looks much bigger than to a native of New York who may be a next-door neighbor to some Morgan or Rockefeller. Besides, the opinion of the highest telephone authority in the world that my solution of the extended La Grangian problem had a very important technical value was much more gratifying to me than all the money in the world.

In Europe, and particularly in England, the invention came as a surprise; they did not expect an American to make an invention which required so much mathematical analysis of electrical motions, to which the American physicist had contributed very little, whereas Vaschy and Heaviside had written volumes about it. But these writers had paid too little attention to classical writers like La Grange, Thomson, and Kirchhoff. The construction of the inductance-coil required almost as much mathematical analysis as the dynamical theory of the invention, and the method of testing it also was new to the telephone engineers. The coil is now known all over the world as the Pupin coil, and many people think that the coil itself is the invention.

When it became known that I had studied at the Universities of Cambridge and of Berlin, my English and German friends claimed the credit of the invention for the scientific training which I had received at their universities. I think the French had a better claim, because it was La Grange who helped me more than any other mathematical reading. As a matter of fact, the engineers of the American Telephone and Telegraph Company and the herdsmen of Idvor deserve most of the credit. The first formulated the problem the solution of which led to the invention, and the second taught me the art of signalling through the ground which guided me to the physical principle which underlies the invention.

A vice-president of the American Telephone and Telegraph Company, who is a very high authority in telephony, informed me recently that one way to describe, roughly, the value of the invention is as follows: If during the past twenty-two years his company had been compelled to extend its network of conductors so as to give, without employing my invention, the same service which it is giving to-day, it would have had to spend at least one hundred million dollars more than it has actually expended. But after quoting him I wish to call attention to a fact which the public often overlooks. I ask, where are those one hundred million dollars which the invention has saved? I know that not even a microscopic part of them is in the pockets of the inventor. I have figured out also, with the same accuracy with which I once figured out the invention, that those hundred million dollars are not in the pockets of the telephone company. They must be, therefore, in the pockets of the American public. The invention made it possible to give the telephone service, which is now being given, at a lower rate than would have been possible if one hundred million dollars more had been spent. Every good invention benefits the public immeasurably more than it benefits the inventor or the corporation which exploits the invention. I certainly consider myself a public benefactor, and the National Institute of Social Sciences called me so when it gave me a gold medal almost as big as the full moon. But this gift would have made me much more happy if the institute had at the same time given another gold medal to the American Telephone and Telegraph Company.

Some fifteen years ago, when Frederick P. Fish, the famous patent attorney, was the president of the American Telephone and Telegraph Company, I asked him in the course of a conversation whether he would like to sell me back my invention. “Yes,” said he, “but only if you will buy the whole telephone company with it. Our whole plant has been adjusted to the invention, and when one goes the other also must go. The invention has enabled us to detect many defects in our transmission system, and if it had done nothing else than that it would have been worth at least ten times what we paid you. It is the greatest faultfinder that we ever struck, and it is the only form of faultfinder for which we have any use.” A progressive industrial organization courts the criticism of an accurate and friendly faultfinder. It leads to research and development, and that supplies the vital energy to every industry. Twenty-five years ago the American Telephone and Telegraph Company had a small laboratory in Boston, where it did all its scientific research and development. But, presently, faultfinders like my inventions moved into the peaceful and drowsy precincts of that tiny laboratory, and stirred up the engineers and the board of directors. I am very happy whenever I think that, possibly, my inventions have contributed some to this healthful stirring up. What was the result? To-day the American Telephone and Telegraph Company and the affiliated Western Electric Company employ about three thousand persons at an expenditure of some nine million dollars annually in their research and development work. The scientific research work at our universities looks very modest in comparison with operations of this kind. Young men of the highest academic training and splendid talents are busy day and night exploring the hidden treasures on the boundary-lines between the various sciences and the science and art of telephony, and their discoveries, I am sure, are the best investment of this great industrial organization. For instance, their development of the many details in my invention have been wonderful, and give testimony of the highest kind to the excellence of their scientific research. It is not so much the occasional inventor who nurses a great art like telephony and makes it grow beyond all our expectations, as it is the intelligence of a well-organized and liberally supported research laboratory. When I think of that I am perfectly convinced that very few of the great advances in the telephone art would have happened under government ownership. That explains why telephony is practically dead in most European countries. What little life it has in Europe is due to the American research in the above-mentioned laboratories.

The General Electric Company, The Westinghouse Company, the Eastman Kodak Company, and many other industrial corporations in this country are supporting similar research and development laboratories, where scientific men of the highest training are busily exploring what Helmholtz called the rich territories near the boundary-lines of the various sciences and of the science forming the foundation of their respective industries. This reminds me of what I saw on a much smaller scale in Germany, nearly forty years ago, when I was a student there. We copied Germany’s good example, but are leading now, and the pace is so swift that Europeans are dropping behind us very rapidly. The spirit of scientific research has moved into our universities, and from the universities it has moved into our industrial organizations. Industrial research is making bigger and bigger demands upon the universities for highly trained scientific research men; the demand is larger than the supply, and because the industries can pay much higher salaries than the universities can much difficulty has been experienced in inducing bright and promising young scientists to pursue the academic career of a teacher. The quality of the scientific teacher in the university is temporarily deteriorating, that of the industrial research scientist is steadily rising; on the whole, however, the country is a gainer. The university man in the industries will transplant there the scientific idealism of the university. The captains of our leading industries already admit, as will be pointed out below, that the cultivation of scientific idealism is the best policy for our American industries. Listen to the papers which are read by their research men and you will see that the industries actually practise the new gospel of scientific idealism which they are preaching.

But I must not depart too far from the main thread of my story. When it became known that the American Telephone and Telegraph Company had acquired the rights to my _high inductance wave conductors_, all kinds of legends were told about the invention and the fabulous price paid for it. Newspapers love legends, because the public loves them. The public is a child which loves to listen to fairy-tales. The only good that this publicity did was to help me sell my inventions relating to electrical tuning and rectification in wireless telegraphy. These lay idle for quite a number of years, and waited for further developments in the wireless art before they could be employed to advantage. Electrical tuning and electrical rectification are fundamental operations in the radio art to-day, but the wireless telegraphy of the early days is a distant and poor relation of our present radio art. The world had to wait quite some time for new discoveries which gave birth to the epoch-making inventions of new men, like Lee De Forest and Major E. H. Armstrong. It had to wait also for the great industrial research laboratories before electrical tuning and rectification could come into their own. In the early days of wireless telegraphy I suggested several novel developments which might give a fair chance to tuning and rectification, but I attracted scarcely any attention. The legends just mentioned made people a little more attentive.

One morning a man stepped suddenly into my office at Columbia, and introduced himself as Mr. Green, organizer and promoter of the Marconi Company of America. He was full of action and looked like business. “Are your wireless inventions for sale?” asked Mr. Green, without much preliminary talk. “They are,” I answered, and I felt that my heart was quivering on account of the unexpected blow which this laconic question had given it. “How much?” asked Mr. Green. I gave him the first figure that came into my head, and he, not a bit daunted, asked whether I would take one-half in cash and one-half in stock. I asked him twenty-four hours to decide. “All right,” said he, and promised to call again the next day at the same hour. I should have been perfectly satisfied to accept the cash offer and close the deal even without the stock, but I was afraid that any over-anxiety on my part might scare him away. The next day he called and the deal was closed, he making a certain cash payment immediately and I agreeing to furnish certain documents before the final payment was made. I was fairly well acquainted with trading transactions in my native land; my father often took me to market-places where he bought and sold cattle and horses. I remember well the never-ending bartering which very often ended in a fizzle. The nearer you get to Constantinople the worse becomes the custom of this Oriental method of trading. Mr. Green had none of that Orientalism, and his utter indifference to the figures involved in the deal astonished me. He also took it for granted that I could and would perform all the fine things which I promised to perform; that was very flattering to me, but I was too much of an Oriental to accept, without some apprehension, his apparently implicit trust in me.

This reminds me of an incident which happened eight years ago. The Serbian Government cabled me to make a contract for five thousand tons of lard; I was its only diplomatic and consular representative in America during the war. I called up the representatives of Swift and of Armour and told them over the telephone what was wanted, requesting them to file their bids in forty-eight hours. Two days later I met them in my office and some Serbian war commissioners happened to be present. The contract was closed in less than thirty minutes, and when I told the commissioners that it involved one million dollars they crossed themselves in utter amazement. In Belgrade, they assured me, the closing of such a contract would have required at least a month. I astonished them as much as Mr. Green had astonished me, and the lard transaction reminded me strongly of my deal with the Marconi Company of America. Of course, lard handled by Swifts or Armours is a much simpler proposition than a lot of belated inventions relating to electrical tuning and electrical rectification for which there was not yet a crying demand.

A few months after my deal with Green I was in Berlin, by invitation, for the purpose of negotiating, for my telephone invention, a business agreement with the famous electrical firm of Siemens and Halske. It was founded by Werner von Siemens, whom I had met fifteen years before through the kind introduction of my teacher, Excellenz von Helmholtz. During the negotiations which lasted one month I met the directors of this corporation in almost daily conferences, which lasted never less than an hour and very often several hours. Every detail of my invention was thoroughly discussed both from the purely scientific and from the engineering side, in its relation to the earlier publications which had a bearing upon it, in its legal aspects as determined by the German patent laws; and finally the financial side was carefully considered and definitely settled. There was no bartering of any kind, neither was anything taken for granted. Contrary to our American custom, the negotiations were directly between the inventor and the scientific experts. The lawyers had very little to say, and spoke only when the experts needed and asked for their opinion. When I recall my negotiations with the American Telephone and Telegraph Company, I remember nothing but lawyers. The negotiations with Siemens and Halske recall scientific experts only; the negotiations with the Marconi Company of America recall only Green. At the close of the Berlin conferences and negotiations I was perfectly certain that I had accomplished something; I understood my invention better than I had ever understood it before, and I was perfectly certain that the scientists of Siemens and Halske understood it just as well. Their popular descriptions of it were better than anything I had ever done myself. They also gave it a new name, and called telephone conductors employing the invention “_pupinizierte linien_.” The French followed suit, and called them “_les lignes pupinizé_.” These two new words coined in my honor will last as long as the invention lasts, and so far there is no sign that it will be superseded soon by some other invention. Its simplicity and effectiveness give it much vitality.

After the completion of my negotiations in Berlin, the Siemens and Halske engineers took me to Vienna for the purpose of introducing me to the high officers in the Austrian Imperial Cabinet who guided the destinies of the telephone system of the Austrian Empire. They were glad, they said, to meet a native of Banat, a former subject of Austria, who had made so important an invention, and they assured me that their policy with regard to it would be guided entirely by the decision of the Berlin experts. Vienna did not seem to have a mind of its own, and all its thinking apparently was done for it by the experts in Berlin. I was quite elated by the idea that the Berlin experts who did the thinking for the Austrian Empire had been most happy to spend a whole month with me in daily conferences, eager to learn all they could from me. I could not help exclaiming: “Oh, what a fortunate thing it was that in my early youth I ran away from this moribund Empire, and landed in a country of opportunities, where every individual thinks through his own head and carries his load on his own back.” Germany, at that time, was so vigorous that she did not hesitate to do all the thinking and hustling for Austria as well as for Turkey, and did not realize that she was carrying around two corpses which could not be revived by even the combined vitality of all the young and vigorous nations, like the United States of America and United Germany.