Of all his inventions, it is doubtful whether any one of them has called forth more original thought, work, perseverance, ingenuity, and monumental patience than the one we are now dealing with. One of his a.s.sociates who has been through the many years of the storage-battery drudgery with him said: "If Edison's experiments, investigations, and work on this storage battery were all that he had ever done, I should say that he was not only a notable inventor, but also a great man. It is almost impossible to appreciate the enormous difficulties that have been overcome."

From a beginning which was made practically in the dark, it was not until he had completed more than ten thousand experiments that he obtained any positive preliminary results whatever. Through all this vast amount of research there had been no previous signs of the electrical action he was looking for. These experiments had extended over many months of constant work by day and night, but there was no breakdown of Edison's faith in ultimate success--no diminution of his sanguine and confident expectations. The failure of an experiment simply meant to him that he had found something else that would not work, thus bringing the possible goal a little nearer by a process of painstaking elimination.

Now, however, after these many months of arduous toil, in which he had examined and tested practically all the known elements in numerous chemical combinations, the electric action he sought for had been obtained, thus affording him the first inkling of the secret that he had industriously tried to wrest from Nature. It should be borne in mind that from the very outset Edison had disdained any intention of following in the only tracks then known by employing lead and sulphuric acid as the components of a successful storage battery. Impressed with what he considered the serious inherent defects of batteries made of these materials, and the tremendously complex nature of the chemical reactions taking place in all types of such cells, he determined boldly at the start that he would devise a battery without lead, and one in which an alkaline solution could be used--a form which would, he firmly believed, be inherently less subject to decay and dissolution than the standard type, which after many setbacks had finally won its way to an annual production of many thousands of cells, worth millions of dollars.

Two or three thousand of the first experiments followed the line of his well-known primary battery in the attempted employment of copper oxide as an element in a new type of storage cell; but its use offered no advantages, and the hunt was continued in other directions and pursued until Edison satisfied himself by a vast number of experiments that nickel and iron possessed the desirable qualifications he was in search of.

This immense amount of investigation which had consumed so many months of time, and which had culminated in the discovery of a series of reactions between nickel and iron that bore great promise, brought Edison merely within sight of a strange and hitherto unexplored country. Slowly but surely the results of the last few thousands of his preliminary experiments had pointed inevitably to a new and fruitful region ahead. He had discovered the hidden pa.s.sage and held the clew which he had so industriously sought. And now, having outlined a definite path, Edison was all afire to push ahead vigorously in order that he might enter in and possess the land.

It is a trite saying that "history repeats itself," and certainly no axiom carries more truth than this when applied to the history of each of Edison's important inventions. The development of the storage battery has been no exception; indeed, far from otherwise, for in the ten years that have elapsed since the time he set himself and his mechanics, chemists, machinists, and experimenters at work to develop a practical commercial cell, the old story of incessant and persistent efforts so manifest in the working out of other inventions was fully repeated.

Very soon after he had decided upon the use of nickel and iron as the elemental metals for his storage battery, Edison established a chemical plant at Silver Lake, New Jersey, a few miles from the Orange laboratory, on land purchased some time previously. This place was the scene of the further experiments to develop the various chemical forms of nickel and iron, and to determine by tests what would be best adapted for use in cells manufactured on a commercial scale. With a little handful of selected experimenters gathered about him, Edison settled down to one of his characteristic struggles for supremacy. To some extent it was a revival of the old Menlo Park days (or, rather, nights).

Some of these who had worked on the preliminary experiments, with the addition of a few new-comers, toiled together regardless of pa.s.sing time and often under most discouraging circ.u.mstances, but with that remarkable esprit de corps that has ever marked Edison's relations with his co-workers, and that has contributed so largely to the successful carrying out of his ideas.

The group that took part in these early years of Edison's arduous labors included his old-time a.s.sistant, Fred Ott, together with his chemist, J. W. Aylsworth, as well as E. J. Ross, Jr., W. E. Holland, and Ralph Arbogast, and a little later W. G. Bee, all of whom have grown up with the battery and still devote their energies to its commercial development. One of these workers, relating the strenuous experiences of these few years, says: "It was hard work and long hours, but still there were some things that made life pleasant. One of them was the supper-hour we enjoyed when we worked nights. Mr. Edison would have supper sent in about midnight, and we all sat down together, including himself. Work was forgotten for the time, and all hands were ready for fun. I have very pleasant recollections of Mr. Edison at these times. He would always relax and help to make a good time, and on some occasions I have seen him fairly overflow with animal spirits, just like a boy let out from school. After the supper-hour was over, however, he again became the serious, energetic inventor, deeply immersed in the work at hand.

"He was very fond of telling and hearing stories, and always appreciated a joke. I remember one that he liked to get off on us once in a while.

Our lighting plant was in duplicate, and about 12.30 or 1 o'clock in the morning, at the close of the supper-hour, a change would be made from one plant to the other, involving the gradual extinction of the electric lights and their slowly coming up to candle-power again, the whole change requiring probably about thirty seconds. Sometimes, as this was taking place, Edison would fold his hands, compose himself as if he were in sound sleep, and when the lights were full again would apparently wake up, with the remark, 'Well, boys, we've had a fine rest; now let's pitch into work again.'"

Another interesting and amusing reminiscence of this period of activity has been gathered from another of the family of experimenters: "Sometimes, when Mr. Edison had been working long hours, he would want to have a short sleep. It was one of the funniest things I ever witnessed to see him crawl into an ordinary roll-top desk and curl up and take a nap. If there was a sight that was still more funny, it was to see him turn over on his other side, all the time remaining in the desk. He would use several volumes of Watts's Dictionary of Chemistry for a pillow, and we fellows used to say that he absorbed the contents during his sleep, judging from the flow of new ideas he had on waking."

Such incidents as these serve merely to ill.u.s.trate the lighter moments that stand out in relief against the more sombre background of the strenuous years, for, of all the absorbingly busy periods of Edison's inventive life, the first five years of the storage-battery era was one of the very busiest of them all. It was not that there remained any basic principle to be discovered or simplified, for that had already been done; but it was in the effort to carry these principles into practice that there arose the numerous difficulties that at times seemed insurmountable. But, according to another co-worker, "Edison seemed pleased when he used to run up against a serious difficulty. It would seem to stiffen his backbone and make him more prolific of new ideas.

For a time I thought I was foolish to imagine such a thing, but I could never get away from the impression that he really appeared happy when he ran up against a serious snag. That was in my green days, and I soon learned that the failure of an experiment never discourages him unless it is by reason of the carelessness of the man making it. Then Edison gets disgusted. If it fails on its merits, he doesn't worry or fret about it, but, on the contrary, regards it as a useful fact learned; remains cheerful and tries something else. I have known him to reverse an unsuccessful experiment and come out all right."

To follow Edison's trail in detail through the innumerable twists and turns of his experimentation and research on the storage battery, during the past ten years, would not be in keeping with the scope of this narrative, nor would it serve any useful purpose. Besides, such details would fill a big volume. The narrative, however, would not be complete without some mention of the general outline of his work, and reference may be made briefly to a few of the chief items. And lest the reader think that the word "innumerable" may have been carelessly or hastily used above, we would quote the reply of one of the laboratory a.s.sistants when asked how many experiments had been made on the Edison storage battery since the year 1900: "Goodness only knows! We used to number our experiments consecutively from 1 to 10,000, and when we got up to 10,000 we turned back to 1 and ran up to 10,000 again, and so on. We ran through several series--I don't know how many, and have lost track of them now, but it was not far from fifty thousand."

From the very first, Edison's broad idea of his storage battery was to make perforated metallic containers having the active materials packed therein; nickel hydrate for the positive and iron oxide for the negative plate. This plan has been adhered to throughout, and has found its consummation in the present form of the completed commercial cell, but in the middle ground which stands between the early crude beginnings and the perfected type of to-day there lies a world of original thought, patient plodding, and achievement.

The first necessity was naturally to obtain the best and purest compounds for active materials. Edison found that comparatively little was known by manufacturing chemists about nickel and iron oxides of the high grade and purity he required. Hence it became necessary for him to establish his own chemical works and put them in charge of men specially trained by himself, with whom he worked. This was the plant at Silver Lake, above referred to. Here, for several years, there was ceaseless activity in the preparation of these chemical compounds by every imaginable process and subsequent testing. Edison's chief chemist says: "We left no stone unturned to find a way of making those chemicals so that they would give the highest results. We carried on the experiments with the two chemicals together. Sometimes the nickel would be ahead in the tests, and then again it would fall behind. To stimulate us to greater improvement, Edison hung up a card which showed the results of tests in milliampere-hours given by the experimental elements as we tried them with the various grades of nickel and iron we had made. This stirred up a great deal of ambition among the boys to push the figures up. Some of our earliest tests showed around 300, but as we improved the material, they gradually crept up to over 500. Just about that time Edison made a trip to Canada, and when he came back we had made such good progress that the figures had crept up to about 1000. I well remember how greatly he was pleased."

In speaking of the development of the negative element of the battery, Mr. Aylsworth said: "In like manner the iron element had to be developed and improved; and finally the iron, which had generally enjoyed superiority in capacity over its companion, the nickel element, had to go in training in order to retain its lead, which was imperative, in order to produce a uniform and constant voltage curve. In talking with me one day about the difficulties under which we were working and contrasting them with the phonograph experimentation, Edison said: 'In phonographic work we can use our ears and our eyes, aided with powerful microscopes; but in the battery our difficulties cannot be seen or heard, but must be observed by our mind's eye!' And by reason of the employment of such vision in the past, Edison is now able to see quite clearly through the forest of difficulties after eliminating them one by one."

The size and shape of the containing pockets in the battery plates or elements and the degree of their perforation were matters that received many years of close study and experiment; indeed, there is still to-day constant work expended on their perfection, although their present general form was decided upon several years ago. The mechanical construction of the battery, as a whole, in its present form, compels instant admiration on account of its beauty and completeness. Mr. Edison has spared neither thought, ingenuity, labor, nor money in the effort to make it the most complete and efficient storage cell obtainable, and the results show that his skill, judgment, and foresight have lost nothing of the power that laid the foundation of, and built up, other great arts at each earlier stage of his career.

Among the complex and numerous problems that presented themselves in the evolution of the battery was the one concerning the internal conductivity of the positive unit. The nickel hydrate was a poor electrical conductor, and although a metallic nickel pocket might be filled with it, there would not be the desired electrical action unless a conducting substance were mixed with it, and so incorporated and packed that there would be good electrical contact throughout.

This proved to be a most knotty and intricate puzzle--tricky and evasive--always leading on and promising something, and at the last slipping away leaving the work undone. Edison's remarkable patience and persistence in dealing with this trying problem and in finally solving it successfully won for him more than ordinary admiration from his a.s.sociates. One of them, in speaking of the seemingly interminable experiments to overcome this trouble, said: "I guess that question of conductivity of the positive pocket brought lots of gray hairs to his head. I never dreamed a man could have such patience and perseverance.

Any other man than Edison would have given the whole thing up a thousand times, but not he! Things looked awfully blue to the whole bunch of us many a time, but he was always hopeful. I remember one time things looked so dark to me that I had just about made up my mind to throw up my job, but some good turn came just then and I didn't. Now I'm glad I held on, for we've got a great future."

The difficulty of obtaining good electrical contact in the positive element was indeed Edison's chief trouble for many years. After a great amount of work and experimentation he decided upon a certain form of graphite, which seemed to be suitable for the purpose, and then proceeded to the commercial manufacture of the battery at a special factory in Glen Ridge, New Jersey, installed for the purpose. There was no lack of buyers, but, on the contrary, the factory was unable to turn out batteries enough. The newspapers had previously published articles showing the unusual capacity and performance of the battery, and public interest had thus been greatly awakened.

Notwithstanding the establishment of a regular routine of manufacture and sale, Edison did not cease to experiment for improvement. Although the graphite apparently did the work desired of it, he was not altogether satisfied with its performance and made extended trials of other substances, but at that time found nothing that on the whole served the purpose better. Continuous tests of the commercial cells were carried on at the laboratory, as well as more practical and heavy tests in automobiles, which were constantly kept running around the adjoining country over all kinds of roads. All these tests were very closely watched by Edison, who demanded rigorously that the various trials of the battery should be carried on with all strenuousness so as to get the utmost results and develop any possible weakness. So insistent was he on this, that if any automobile should run several days without bursting a tire or breaking some part of the machine, he would accuse the chauffeur of picking out easy roads.

After these tests had been going on for some time, and some thousands of cells had been sold and were giving satisfactory results to the purchasers, the test sheets and experience gathered from various sources pointed to the fact that occasionally a cell here and there would show up as being short in capacity. Inasmuch as the factory processes were very exact and carefully guarded, and every cell was made as uniform as human skill and care could provide, there thus arose a serious problem.

Edison concentrated his powers on the investigation of this trouble, and found that the chief cause lay in the graphite. Some other minor matters also attracted his attention. What to do, was the important question that confronted him. To shut down the factory meant great loss and apparent failure. He realized this fully, but he also knew that to go on would simply be to increase the number of defective batteries in circulation, which would ultimately result in a permanent closure and real failure. Hence he took the course which one would expect of Edison's common sense and directness of action. He was not satisfied that the battery was a complete success, so he shut down and went to experimenting once more.

"And then," says one of the laboratory men, "we started on another series of record-breaking experiments that lasted over five years.

I might almost say heart-breaking, too, for of all the elusive, disappointing things one ever hunted for that was the worst. But secrets have to be long-winded and roost high if they want to get away when the 'Old Man' goes hunting for them. He doesn't get mad when he misses them, but just keeps on smiling and firing, and usually brings them into camp.

That's what he did on the battery, for after a whole lot of work he perfected the nickel-flake idea and process, besides making the great improvement of using tubes instead of flat pockets for the positive. He also added a minor improvement here and there, and now we have a finer battery than we ever expected."

In the interim, while the experimentation of these last five years was in progress, many customers who had purchased batteries of the original type came knocking at the door with orders in their hands for additional outfits wherewith to equip more wagons and trucks. Edison expressed his regrets, but said he was not satisfied with the old cells and was engaged in improving them. To which the customers replied that THEY were entirely satisfied and ready and willing to pay for more batteries of the same kind; but Edison could not be moved from his determination, although considerable pressure was at times brought to bear to sway his decision.

Experiment was continued beyond the point of peradventure, and after some new machinery had been built, the manufacture of the new type of cell was begun in the early summer of 1909, and at the present writing is being extended as fast as the necessary additional machinery can be made. The product is shipped out as soon as it is completed.

The nickel flake, which is Edison's ingenious solution of the conductivity problem, is of itself a most interesting product, intensely practical in its application and fascinating in its manufacture. The flake of nickel is obtained by electroplating upon a metallic cylinder alternate layers of copper and nickel, one hundred of each, after which the combined sheet is stripped from the cylinder. So thin are the layers that this sheet is only about the thickness of a visiting-card, and yet it is composed of two hundred layers of metal. The sheet is cut into tiny squares, each about one-sixteenth of an inch, and these squares are put into a bath where the copper is dissolved out. This releases the layers of nickel, so that each of these small squares becomes one hundred tiny sheets, or flakes, of pure metallic nickel, so thin that when they are dried they will float in the air, like thistle-down.

In their application to the manufacture of batteries, the flakes are used through the medium of a special machine, so arranged that small charges of nickel hydrate and nickel flake are alternately fed into the pockets intended for positives, and tamped down with a pressure equal to about four tons per square inch. This insures complete and perfect contact and consequent electrical conductivity throughout the entire unit.

The development of the nickel flake contains in itself a history of patient investigation, labor, and achievement, but we have not s.p.a.ce for it, nor for tracing the great work that has been done in developing and perfecting the numerous other parts and adjuncts of this remarkable battery. Suffice it to say that when Edison went boldly out into new territory, after something entirely unknown, he was quite prepared for hard work and exploration. He encountered both in unstinted measure, but kept on going forward until, after long travel, he had found all that he expected and accomplished something more beside. Nature DID respond to his whole-hearted appeal, and, by the time the hunt was ended, revealed a good storage battery of entirely new type. Edison not only recognized and took advantage of the principles he had discovered, but in adapting them for commercial use developed most ingenious processes and mechanical appliances for carrying his discoveries into practical effect. Indeed, it may be said that the invention of an enormous variety of new machines and mechanical appliances rendered necessary by each change during the various stages of development of the battery, from first to last, stands as a lasting tribute to the range and versatility of his powers.

It is not within the scope of this narrative to enter into any description of the relative merits of the Edison storage battery, that being the province of a commercial catalogue. It does, however, seem entirely allowable to say that while at the present writing the tests that have been made extend over a few years only, their results and the intrinsic value of this characteristic Edison invention are of such a substantial nature as to point to the inevitable growth of another great industry arising from its manufacture, and to its wide-spread application to many uses.

The princ.i.p.al use that Edison has had in mind for his battery is transportation of freight and pa.s.sengers by truck, automobile, and street-car. The greatly increased capacity in proportion to weight of the Edison cell makes it particularly adaptable for this cla.s.s of work on account of the much greater radius of travel that is possible by its use. The latter point of advantage is the one that appeals most to the automobilist, as he is thus enabled to travel, it is a.s.serted, more than three times farther than ever before on a single charge of the battery.

Edison believes that there are important advantages possible in the employment of his storage battery for street-car propulsion. Under the present system of operation, a plant furnishing the electric power for street railways must be large enough to supply current for the maximum load during "rush hours," although much of the machinery may be lying idle and unproductive in the hours of minimum load. By the use of storage-battery cars, this immense and uneconomical maximum investment in plant can be cut down to proportions of true commercial economy, as the charging of the batteries can be conducted at a uniform rate with a reasonable expenditure for generating machinery. Not only this, but each car becomes an independently moving unit, not subject to delay by reason of a general breakdown of the power plant or of the line. In addition to these advantages, the streets would be freed from their burden of trolley wires or conduits. To put his ideas into practice, Edison built a short railway line at the Orange works in the winter of 1909-10, and, in co-operation with Mr. R. H. Beach, constructed a special type of street-car, and equipped it with motor, storage battery, and other necessary operating devices. This car was subsequently put upon the street-car lines in New York City, and demonstrated its efficiency so completely that it was purchased by one of the street-car companies, which has since ordered additional cars for its lines. The demonstration of this initial car has been watched with interest by many railroad officials, and its performance has been of so successful a nature that at the present writing (the summer of 1910) it has been necessary to organize and equip a preliminary factory in which to construct many other cars of a similar type that have been ordered by other street-railway companies. This enterprise will be conducted by a corporation which has been specially organized for the purpose. Thus, there has been initiated the development of a new and important industry whose possible ultimate proportions are beyond the range of present calculation. Extensive as this industry may become, however, Edison is firmly convinced that the greatest field for his storage battery lies in its adaptation to commercial trucking and hauling, and to pleasure vehicles, in comparison with which the street-car business even with its great possibilities--will not amount to more than 1 per cent.

Edison has pithily summed up his work and his views in an article on "The To-Morrows of Electricity and Invention" in Popular Electricity for June, 1910, in which he says: "For years past I have been trying to perfect a storage battery, and have now rendered it entirely suitable to automobile and other work. There is absolutely no reason why horses should be allowed within city limits; for between the gasoline and the electric car, no room is left for them. They are not needed. The cow and the pig have gone, and the horse is still more undesirable. A higher public ideal of health and cleanliness is working toward such banishment very swiftly; and then we shall have decent streets, instead of stables made out of strips of cobblestones bordered by sidewalks. The worst use of money is to make a fine thoroughfare, and then turn it over to horses. Besides that, the change will put the humane societies out of business. Many people now charge their own batteries because of lack of facilities; but I believe central stations will find in this work very soon the largest part of their load. The New York Edison Company, or the Chicago Edison Company, should have as much current going out for storage batteries as for power motors; and it will be so some near day."

CHAPTER XXIII

MISCELLANEOUS INVENTIONS

IT has been the endeavor in this narrative to group Edison's inventions and patents so that his work in the different fields can be studied independently and separately. The history of his career has therefore fallen naturally into a series of chapters, each aiming to describe some particular development or art; and, in a way, the plan has been helpful to the writers while probably useful to the readers. It happens, however, that the process has left a vast ma.s.s of discovery and invention wholly untouched, and relegates to a concluding brief chapter some of the most interesting episodes of a fruitful life. Any one who will turn to the list of Edison patents at the end of the book will find a large number of things of which not even casual mention has been made, but which at the time occupied no small amount of the inventor's time and attention, and many of which are now part and parcel of modern civilization. Edison has, indeed, touched nothing that he did not in some way improve. As Th.o.r.eau said: "The laws of the Universe are not indifferent, but are forever on the side of the most sensitive," and there never was any one more sensitive to the defects of every art and appliance, nor any one more active in applying the law of evolution.

It is perhaps this many-sidedness of Edison that has impressed the mult.i.tude, and that in the "popular vote" taken a couple of years ago by the New York Herald placed his name at the head of the list of ten greatest living Americans. It is curious and pertinent to note that a similar plebiscite taken by a technical journal among its expert readers had exactly the same result. Evidently the public does not agree with the opinion expressed by the eccentric artist Blake in his "Marriage of Heaven and h.e.l.l," when he said: "Improvement makes strange roads; but the crooked roads without improvements are roads of Genius."

The product of Edison's brain may be divided into three cla.s.ses. The first embraces such arts and industries, or such apparatus, as have already been treated. The second includes devices like the tasimeter, phonomotor, odoroscope, etc., and others now to be noted. The third embraces a number of projected inventions, partially completed investigations, inventions in use but not patented, and a great many caveats filed in the Patent Office at various times during the last forty years for the purpose of protecting his ideas pending their contemplated realization in practice. These caveats served their purpose thoroughly in many instances, but there have remained a great variety of projects upon which no definite action was ever taken. One ought to add the contents of an unfinished piece of extraordinary fiction based wholly on new inventions and devices utterly unknown to mankind. Some day the novel may be finished, but Edison has no inclination to go back to it, and says he cannot understand how any man is able to make a speech or write a book, for he simply can't do it.

After what has been said in previous chapters, it will not seem so strange that Edison should have hundreds of dormant inventions on his hands. There are human limitations even for such a tireless worker as he is. While the preparation of data for this chapter was going on, one of the writers in discussing with him the vast array of unexploited things said: "Don't you feel a sense of regret in being obliged to leave so many things uncompleted?" To which he replied: "What's the use? One lifetime is too short, and I am busy every day improving essential parts of my established industries." It must suffice to speak briefly of a few leading inventions that have been worked out, and to dismiss with scant mention all the rest, taking just a few items, as typical and suggestive, especially when Edison can himself be quoted as to them.

Incidentally it may be noted that things, not words, are referred to; for Edison, in addition to inventing the apparatus, has often had to coin the word to describe it. A large number of the words and phrases in modern electrical parlance owe their origin to him. Even the "call-word"

of the telephone, "h.e.l.lo!" sent tingling over the wire a few million times daily was taken from Menlo Park by men installing telephones in different parts of the world, men who had just learned it at the laboratory, and thus made it a universal sesame for telephonic conversation.

It is hard to determine where to begin with Edison's miscellaneous inventions, but perhaps telegraphy has the "right of line," and Edison's work in that field puts him abreast of the latest wireless developments that fill the world with wonder. "I perfected a system of train telegraphy between stations and trains in motion whereby messages could be sent from the moving train to the central office; and this was the forerunner of wireless telegraphy. This system was used for a number of years on the Lehigh Valley Railroad on their construction trains. The electric wave pa.s.sed from a piece of metal on top of the car across the air to the telegraph wires; and then proceeded to the despatcher's office. In my first experiments with this system I tried it on the Staten Island Railroad, and employed an operator named King to do the experimenting. He reported results every day, and received instructions by mail; but for some reason he could send messages all right when the train went in one direction, but could not make it go in the contrary direction. I made suggestions of every kind to get around this phenomenon. Finally I telegraphed King to find out if he had any suggestions himself; and I received a reply that the only way he could propose to get around the difficulty was to put the island on a pivot so it could be turned around! I found the trouble finally, and the practical introduction on the Lehigh Valley road was the result. The system was sold to a very wealthy man, and he would never sell any rights or answer letters. He became a spiritualist subsequently, which probably explains it." It is interesting to note that Edison became greatly interested in the later developments by Marconi, and is an admiring friend and adviser of that well-known inventor.

The earlier experiments with wireless telegraphy at Menlo Park were made at a time when Edison was greatly occupied with his electric-light interests, and it was not until the beginning of 1886 that he was able to spare the time to make a public demonstration of the system as applied to moving trains. Ezra T. Gilliland, of Boston, had become a.s.sociated with him in his experiments, and they took out several joint patents subsequently. The first practical use of the system took place on a thirteen-mile stretch of the Staten Island Railroad with the results mentioned by Edison above.

A little later, Edison and Gilliland joined forces with Lucius J.

Phelps, another investigator, who had been experimenting along the same lines and had taken out several patents. The various interests were combined in a corporation under whose auspices the system was installed on the Lehigh Valley Railroad, where it was used for several years. The official demonstration trip on this road took place on October 6, 1887, on a six-car train running to Easton, Pennsylvania, a distance of fifty-four miles. A great many telegrams were sent and received while the train was at full speed, including a despatch to the "cable king,"

John Pender. London, England, and a reply from him. [17]

[Footnote 17: Broadly described in outline, the system consisted of an induction circuit obtained by laying strips of tin along the top or roof of a railway car, and the installation of a special telegraph line running parallel with the track and strung on poles of only medium height.

The train and also each signalling station were equipped with regulation telegraphic apparatus, such as battery, key, relay, and sounder, together with induction-coil and condenser. In addition, there was a transmitting device in the shape of a musical reed, or buzzer. In practice, this buzzer was continuously operated at high speed by a battery.

Its vibrations were broken by means of a key into long and short periods, representing Morse characters, which were transmitted inductively from the train circuit to the pole line, or vice versa, and received by the operator at the other end through a high-resistance telephone receiver inserted in the secondary circuit of the induction-coil.]

Although the s.p.a.ce between the cars and the pole line was probably not more than about fifty feet, it is interesting to note that in Edison's early experiments at Menlo Park he succeeded in transmitting messages through the air at a distance of 580 feet. Speaking of this and of his other experiments with induction telegraphy by means of kites, communicating from one to the other and thus from the kites to instruments on the earth, Edison said recently: "We only transmitted about two and one-half miles through the kites. What has always puzzled me since is that I did not think of using the results of my experiments on 'etheric force' that I made in 1875. I have never been able to understand how I came to overlook them. If I had made use of my own work I should have had long-distance wireless telegraphy."

In one of the appendices to this book is given a brief technical account of Edison's investigations of the phenomena which lie at the root of modern wireless or "s.p.a.ce" telegraphy, and the attention of the reader is directed particularly to the description and quotations there from the famous note-books of Edison's experiments in regard to what he called "etheric force." It will be seen that as early as 1875 Edison detected and studied certain phenomena--i.e., the production of electrical effects in non-closed circuits, which for a time made him think he was on the trail of a new force, as there was no plausible explanation for them by the then known laws of electricity and magnetism. Later came the magnificent work of Hertz identifying the phenomena as "electromagnetic waves" in the ether, and developing a new world of theory and science based upon them and their production by disruptive discharges.