In addition to all this work, Edison gave attention to many other things. One of them was the first typewriter. In the early 'seventies Mr. D. N. Craig, who was interested in the automatic, brought with him from Milwaukee a Mr. Sholes, who had a wooden model of a machine to which had been given the then new and unfamiliar name of "typewriter." Mr. Craig was interested in the machine and put the model in Edison's hands to perfect.
"This typewriter proved a difficult thing," says Edison, "to make commercial. The alignment of the letters was awful. One letter would be one-sixteenth of an inch above the others, and all the letters wanted to wander out of line. I worked on it till the machine gave fair results. Some were made and used in the office of the Automatic Company. Craig was very sanguine that some day all business letters would be written on a typewriter. He died before that took place; but it gradually made its way. The typewriter I got into commercial shape is now known as the Remington. I now had five shops, and with experimenting on this new scheme I was pretty busy—at least I did not have ennui."
Later on, after the automatic was completed, and Edison was installing the system for the Atlantic and Pacific Telegraph Company he says: "About this time I invented a district messenger call-box system, and organized a company called the Domestic Telegraph Company, and started in to install the system in New York. I had great difficulty in getting subscribers, having tried several canvassers, who, one after the other, failed to get subscribers. When I was about to give it up a test operator named Brown, who was on the Automatic Telegraph wire between New York and Washington, which passed through my Newark shop, asked permission to let him try and see if he couldn't get subscribers. I had very little faith in his ability to get any, but I thought I would give him a chance, as he felt certain of his ability to succeed. He started in, and the results were surprising. Within a month he had procured two hundred subscribers, and the company was a success. I have never quite understood why six men should fail absolutely, while the seventh man should succeed. Perhaps hypnotism would account for it. This company was sold out to the Atlantic and Pacific Company."
This was not the first time that Edison had worked on district messenger signal boxes, for as far back as 1872 he had applied for a patent on a device of this kind. Although he was not the first, he was a very early inventor in this field.
It will be seen, therefore, that not all of his problems and inventions were connected with telegraphy. He seemed to find relief in working on several lines that were quite different and distinct, but all were useful and capable of wide application. For instance, when we take a piece of paraffin paper off candy, chocolate, chewing-gum or other articles, we scarcely realize that it owes its introduction to Mr. Edison. Yet such is the fact, and we relate it in his own modest words: "Toward the latter part of 1875, in the Newark shop, I invented a device for multiplying copies of letters, which I sold to Mr. A. B. Dick, of Chicago, and in the years since it has been introduced universally throughout the world. It is called the mimeograph. I also invented devices for making, and introduced, paraffin paper, now used universally for wrapping up candy, etc."
In the mimeograph a stencil is prepared by writing with a pointed pencil-like stylus on a tough prepared paper placed on a finely grooved steel plate. The pressure of the stylus causes the letters to be punctured in the sheet by a series of minute perforations, thus forming a stencil from which hundreds of copies can be made.
Edison accomplished the same perforating result by two other inventions, one a pneumatic and the other an electric motor. The latter was the one which came into extensive use, and was called the "Edison electric pen." A tiny electric motor was mounted on a pencil-like tube in which a pointed stylus (connected to the motor) traveled to and fro at a very high rate of speed. Current from a battery was supplied to the motor through a flexible cord, and the tube was held and used like a pencil, as in the other case. As many as three thousand copies have been made from such a stencil.
[1]The sand battery is now obsolete. In this type the cell containing the elements was filled with sand, which was kept moist with an electrolyte.
[1]The sand battery is now obsolete. In this type the cell containing the elements was filled with sand, which was kept moist with an electrolyte.
It is well known that to Mr. Alexander Graham Bell belongs the credit for transmitting the articulate voice over an electric circuit by talking against a diaphragm placed in front of an electromagnet. But after Mr. Bell brought out the telephone Mr. Edison made some remarkable improvements.
In the year 1875 Edison took up the study of harmonic telegraphs, in addition to his other work, with the idea of developing a system of multiple transmission by sending sound waves over an electric circuit.
One of the devices he then made is illustrated in an interesting drawing on file at the Orange Laboratory, entitled "First Telephone on Record." This device is described by Edison in a caveat filed in the Patent Office January 14, 1876, a month before Bell filed his application for patent.
Mr. Edison states, however, that while this device was crudely capable of use as a magneto telephone, he did not invent it for transmitting speech, but as an apparatus for analyzing the complex waves arising from various sounds. He did not try the effects of sound waves produced by the human voice until after Bell's discovery was announced, but then found that this device was capable of use as a telephone.
This was a curious coincidence, but it must be understood that Mr. Edison in his testimony and public utterances has always given Mr. Bell full credit for the original discovery of transmitting articulate speech over an electric circuit.
In order to understand the value of Edison's work in this field it should be stated that, while Bell's telephone transmitted speech and other sounds, it was only practicable for short lines. Bell had no separate transmitter, but used a single apparatus both as transmitter and receiver. This instrument was similar to the receiver used to-day, having a metallic diaphragm placed near the pole of a magnet. The vibrations of the diaphragm induced very weak electric impulses in the magnetic coil. These impulses passed over the line to the receiving end, energizing the magnet coil there, and, by varying the magnetism, caused the receiving diaphragm to be similarly vibrated, and thus reproduce the sounds. Under such conditions the telephone would be practicable upon lines of only a few miles in extent, as the amount of power generated by the human voice is necessarily quite limited.
The Western Union Company requested Edison to experiment on the telephone so that it would be commercially practicable. He then went to work with a corps of helpers, and, after months of hard work day and night and the performance of many thousands of experiments, invented the carbon transmitter. This, with his plan of using an induction coil and constant battery current on the line, were the needed elements of success, and it made the telephone a commercial possibility. Every one of the many millions of telephones in use all over the world to-day bears the imprint of Edison's genius in the employment of the principles he then established.
What Edison accomplished was this: Instead of using one single apparatus for transmitting and receiving, he made a separate transmitter of special design. In this he used carbon, which varies in electrical resistance with the pressure applied. The carbon was an electrode in connection with the vibrating diaphragm, and was in a closed circuit through which flowed a battery current. The vibrations of the diaphragm caused variations of pressure on the carbon and consequent variations in the current. These in turn resulted in corresponding impulses in the receiving magnet, and the diaphragm of the receiver was vibrated accordingly, thus reproducing the sounds. Edison's plan also included the passing of the current through an induction coil, the secondary of which was connected with the main line. By this means electrical impulses of enormously high potential are sent out on the main line to the receiving end.
Thus it will be seen that with Bell's telephone the sound-waves themselves generate the electric impulses, which are hence extremely weak. With Edison's telephone the sound-waves actuate an electric valve, so to speak, and permit variations in a current of any desired strength.
Mr. Edison's own story of his telephone work is full of interest: "In 1876 I started again to experiment for the Western Union and Mr. Orton. This time it was the telephone. Bell invented the first telephone, which consisted of the present receiver, used both as a transmitter and a receiver (the magneto type). It was attempted to introduce it commercially, but it failed on account of its faintness and the extraneous sounds which came in on its wire from various causes. Mr. Orton wanted me to take hold of it and make it commercial. As I had also been working on a telegraph system employing tuning-forks, simultaneously with both Bell and Gray, I was pretty familiar with the subject. I started in, and soon produced the carbon transmitter, which is now universally used.
"Tests were made between New York and Philadelphia, also between New York and Washington, using regular Western Union wires. The noises were so great that not a word could be heard with the Bell receiver when used as a transmitter between New York and Newark, New Jersey. Mr. Orton and W. K. Vanderbilt and the board of directors witnessed and took part in the tests of my transmitter. They were successful. The Western Union then put the transmitters on private lines. Mr. Theodore Puskas, of Budapest, Hungary, was the first man to suggest a telephone exchange, and soon after exchanges were established. The telephone department was put in the hands of Hamilton McK. Twombly, Vanderbilt's ablest son-in-law, who made a success of it. The Bell Company, of Boston, also started an exchange, and the fight was on, the Western Union pirating the Bell receiver and the Boston company pirating the Western Union transmitter. About this time I wanted to be taken care of. I threw out hints of this desire. Then Mr. Orton sent for me. He had learned that inventors didn't do business by the regular process, and concluded he would close it right up. He asked me how much I wanted. I had made up my mind it was certainly worth twenty-five thousand dollars if it ever amounted to anything for central station work; so that was the sum I had in mind to obstinately stick to and get. Still it had been an easy job, and only required a few months, and I felt a little shaky and uncertain. So I asked him to make me an offer. He promptly said he would give me one hundred thousand dollars. 'All right,' I said, 'it is yours on one condition, and that is that you do not pay it all at once, but pay me at the rate of six thousand dollars a year for seventeen years—the life of the patent.' He seemed only too pleased to do this, and it was closed. My ambition was about four times too large for my business capacity, and I knew that I would soon spend this money experimenting if I got it all at once; so I fixed it that I couldn't. I saved seventeen years of worry by this stroke."
Edison continued his telephone work through a number of years and made and tested many other kinds of telephones, such as the water telephone, electrostatic telephone, condenser telephone, chemical telephone, various magneto telephones, inertia telephone, mercury telephone, voltaic pile telephone, musical transmitter, and the electromotograph.
The principle of the electromotograph was utilized by him in more ways than one; first of all in telegraphy. Soon after the time he had concluded the telephone arrangement just mentioned a patent was issued to a Mr. Page. This patent was considered very important. It related to the use of a retractile spring to withdraw the armature lever from the magnet of a telegraph or other relay or sounder, and thus controlled the art of telegraphy, except in simple circuits.
"There was no known way," remarks Edison, "whereby this patent could be evaded, and its possessor would eventually control the use of what is known as the relay and sounder, and this was vital to telegraphy. Gould was pounding the Western Union on the Stock Exchange, disturbing its railroad contracts, and, being advised by his lawyers that this patent was of great value, bought it. The moment Mr. Orton heard this he sent for me and explained the situation, and wanted me to go to work immediately and see if I couldn't evade it or discover some other means that could be used in case Gould sustained the patent. It seemed a pretty hard job, because there was no known means of moving a lever at the other end of a telegraph wire except by the use of a magnet. I said I would go at it that night. In experimenting some years previously I had discovered a very peculiar phenomenon, and that was that if a piece of metal connected to a battery was rubbed over a moistened piece of chalk resting on a metal connected to the other pole, when the current passed the friction was greatly diminished. When the current was reversed the friction was greatly increased over what it was when no current was passing. Remembering this, I substituted a piece of chalk, rotated by a small electric motor for the magnet, and connecting a sounder to a metallic finger resting on the chalk, the combination claim of Page was made worthless. A hitherto unknown means was introduced in the electric art. Two or three of the devices were made and tested by the company's expert. Mr. Orton, after he had had me sign the patent application and got it in the Patent Office, wanted to settle for it at once. He asked my price. Again I said, 'Make me an offer.' Again he named one hundred thousand dollars. I accepted, providing he would pay it at the rate of six thousand dollars a year for seventeen years. This was done, and thus, with the telephone money, I received twelve thousand dollars yearly for that period from the Western Union Telegraph Company."
A year or two later the electromotograph principle was again made use of in a curious manner. The telephone was being developed in England, and Edison had made arrangements with Colonel Gouraud, his old associate in the automatic telegraph, to represent his interests.
A company was formed, a large number of instruments were made and sent to London, and prospects were bright. Then there came a threat of litigation from the owners of the Bell patent, and Gouraud found he could not push the enterprise unless he could avoid using what was asserted to be an infringement of the Bell receiver.
He cabled for help to Edison, who sent back word telling him to hold the fort. "I had recourse again," says Edison, "to the phenomenon discovered by me some years previous, that the friction of a rubbing electrode passing over a moist chalk surface was varied by electricity. I devised a telephone receiver which was afterward known as the 'loud-speaking telephone,' or 'chalk receiver.' There was no magnet, simply a diaphragm and a cylinder of compressed chalk about the size of a thimble. A thin spring connected to the center of the diaphragm extended outwardly and rested on the chalk cylinder, and was pressed against it with a pressure equal to that which would be due to a weight of about six pounds. The chalk was rotated by hand. The volume of sound was very great. A person talking into the carbon transmitter in New York had his voice so amplified that he could be heard one thousand feet away in an open field at Menlo Park. This great excess of power was due to the fact that the latter came from the person turning the handle. The voice, instead of furnishing all the power, as with the present receiver, merely controlled the power, just as an engineer working a valve would control a powerful engine.
"I made six of these receivers and sent them in charge of an expert on the first steamer. They were welcomed and tested, and shortly afterward I shipped a hundred more. At the same time I was ordered to send twenty young men, after teaching them to become expert. I set up an exchange of ten instruments around the laboratory. I would then go out and get each one out of order in every conceivable way, cutting the wires of one, short-circuiting another, destroying the adjustment of a third, putting dirt between the electrodes of a fourth, and so on. A man would be sent to each to find out the trouble. When he could find the trouble ten consecutive times, using five minutes each, he was sent to London. About sixty men were sifted to get twenty. Before all had arrived, the Bell Company there, seeing we could not be stopped, entered into negotiations for consolidation. One day I received a cable from Gouraud offering 'thirty thousand' for my interest. I cabled back I would accept. When the draft came I was astonished to find it was for thirty thousand pounds. I had thought it was dollars."
After the consolidation of the Bell and Edison interests in England the chalk receiver was finally abandoned in favor of the Bell receiver—the latter being more simple and cheaper. Extensive litigation with newcomers into the telephone field followed, and Edison's carbon transmitter patent was sustained by the English courts, while Bell's was declared invalid.
In America, the competition between the Western Union and Bell companies, which had been keen and strenuous, was finally brought to an end under an agreement, the former company agreeing to retire from the telephonic field and the latter company agreeing to stay out of the telegraphic field. Through its ownership of Edison's carbon transmitter invention, the Western Union company came to enjoy an annual income of several hundred thousand dollars for some years as a compensation for its retirement from telephony under this agreement.
The principle involved in Edison's carbon-transmitter gave birth to another interesting device called the microphone, by means of which the faintest sounds could be very plainly heard. For instance, the footsteps of a common house-fly make a loud noise when the hearing is assisted by the microphone. As every one knows, the microphone is universally used in our modern radio.
This invention was claimed at the time for Professor Hughes, of England. Whatever credit might be due to him for the form he proposed, a standard history ascribes two original forms of the microphone to Edison, and he himself remarks: "After I sent one of my men over to London especially to show Preece the carbon transmitter, when Hughes first saw it, and heard it—then within a month he came out with the microphone, without any acknowledgment whatever. Published dates will show that Hughes came along after me."
The carbon transmitter has not been the only way in which Edison has utilized the peculiar property that carbon possesses of altering its resistance to the passage of current according to the degree of pressure brought to bear on it.
For his quadruplex system he constructed a rheostat, or resistance box, with a series of silk disks saturated with plumbago and well dried. The pressure on the disks can be regulated by an adjustable screw, and in this way the resistance of the circuit can be varied.
He also developed a "pressure," or carbon, relay, by means of which signals of variable strength can be transferred from one telegraphic circuit to another. The poles of the electromagnet in the local or relay circuit are hollowed out and filled up with carbon disks or powdered plumbago.
If a weak current passes through the relay the armature will be but feebly attracted and will only compress the carbon slightly. Thus the carbon will offer considerable resistance and the signal on the local sounder will be weak.
If, on the contrary, the incoming current be strong, the armature will be strongly attracted, the carbon will be more compressed, thus lowering the resistance and giving a loud signal on the local sounder.
Another beautiful and ingenious use of carbon was made by Edison in an instrument invented by him called the tasimeter. This device was used for indicating most minute degrees of heat, and was so exceedingly sensitive that in one case the heat of rays of light from the remote star Arcturus showed results.
The tasimeter is a very simple instrument. A strip of hard rubber rests vertically on a platinum plate, beneath which is a carbon button, under which again lies another platinum plate. The two plates and the carbon button form part of an electric circuit containing a battery and a galvanometer. Hard rubber is very sensitive to heat, and the slightest rise of temperature causes it to expand, thus increasing the pressure on the carbon button. This produces a variation in resistance shown by the swinging of the galvanometer needle.
This instrument is so sensitive that with a delicate galvanometer the heat of a person's hand thirty feet away will throw the needle off the scale.
If one had never heard a phonograph, it would seem as though it would be impossible to take some pieces of metal and make a machine that would repeat speaking, singing, or instrumental music just like life.
So, before the autumn of 1877, when Edison invented the phonograph, the world thought such a thing was entirely out of the question. Indeed, Edison's own men in his workshop, who had seen him do some wonderful things, thought the idea was absurd when he told them that he was making a machine to reproduce human speech.
One of his men went so far as to bet him a box of cigars that the thing would be an utter failure when finished, but, as every one knows, Edison won the bet, for the very first time the machine was tried it repeated clearly all the words that were spoken into it.
A story has often been told in the newspapers that the invention was made through Edison's finger being pricked by a point attached to a vibrating telephone diaphragm, but this is not true.
The invention was not made through any accident, but was the result of pure reasoning, and in this case, as in many others, fact is more wonderful than fiction. Mr. Edison's own account of the invention of the phonograph is intensely interesting.
"I was experimenting," he says, "on an automatic method of recording telegraph messages on a disk of paper laid on a revolving platen, exactly the same as the disk talking-machine of to-day. The platen had a spiral groove on its surface, like the disk. Over this was placed a circular disk of paper; an electromagnet with the embossing point connected to an arm travelled over the disk, and any signals given through the magnets were embossed on the disk of paper. If this disk was removed from the machine and put on a similar machine provided with a contact point the embossed record would cause the signals to be repeated into another wire. The ordinary speed of telegraphic signals is thirty-five to forty words a minute; but with this machine several hundred words were possible.
"From my experiments on the telephone I knew of the power of a diaphragm to take up sound vibrations, as I had made a little toy which when you recited loudly in the funnel would work a pawl connected to the diaphragm; and this, engaging a ratchet-wheel, served to give continuous rotation to a pulley. This pulley was connected by a cord to a little paper toy representing a man sawing wood. Hence, if one shouted: 'Mary had a little lamb,' etc., the paper man would start sawing wood. I reached the conclusion that if I could record the movements of the diaphragm properly I could cause such records to reproduce the original movements imparted to the diaphragm by the voice, and thus succeed in recording and reproducing the human voice.
"Instead of using a disk I designed a little machine, using a cylinder provided with grooves around the surface. Over this was to be placed tin-foil, which easily received and recorded the movements of the diaphragm. A sketch was made, and the piece-work price, eighteen dollars, was marked on the sketch. I was in the habit of marking the price I would pay on each sketch. If the workman lost, I would pay his regular wages; if he made more than the wages, he kept it. The workman who got the sketch was John Kruesi. I didn't have much faith that it would work, expecting that I might possibly hear a word or so that would give hope of a future for the idea. Kruesi, when he had nearly finished it, asked what it was for. I told him I was going to record talking, and then have the machine talk back. He thought it absurd. However, it was finished; the foil was put on; I then shouted 'Mary had a little lamb,' etc. I adjusted the reproducer, and the machine reproduced it perfectly. I was never so taken back in my life. Everybody was astonished. I was always afraid of things that worked the first time. Long experience proved that there were great drawbacks found generally before they could be made commercial; but here was something there was no doubt of."
No wonder that John Kruesi, as he heard the little machine repeat the words that had been spoken into it, ejaculated in an awe-stricken tone: "Mein Gott im Himmel!" No wonder the "boys" joined hands and danced around Edison, singing and shouting. No wonder that Edison and his associates sat up all night fixing and adjusting it so as to get better and better results—reciting and singing and trying one another's voices and listening with awe and delight as the crude little machine repeated the words spoken or sung into it.
The news quickly became public, and the newspapers of the world published columns about this wonderful invention. Mr. Edison was besieged with letters from every part of the globe. Every one wanted to hear this machine; and in order to satisfy a universal demand for phonographs to be used for exhibition purposes he had a number of them made and turned them over to various individuals, who exhibited them to great crowds around the country. These were the machines in which the record was made on a sheet of tin-foil laid around the cylinder.
They created great excitement both in America and abroad. The announcement of a phonograph concert was sufficient to fill a hall with people who were curious to hear a machine talk and sing.
In the next year, 1878, Edison entered upon his experiments in electric lighting. His work in this field kept him intensely busy for nearly ten years, and the phonograph was laid aside as far as he was concerned.
He had not forgotten it, however, for he had fully realized its tremendous possibilities very quickly after its invention. This is shown by an article he wrote for theNorth American Review, which appeared in the summer of 1878. In that article he predicted the possible uses of the phonograph, many of which have since been fulfilled.
MR. EDISON AT THE CLOSE OF FIVE DAYS AND NIGHTS OF CONTINUED WORK IN PERFECTING THE EARLY WAX-CYLINDER TYPE OF PHONOGRAPH—JUNE 16, 1888This is the longest continuous session of labor he ever performed.
In 1887, having finished the greatest part of his work on the electric light, he turned to the phonograph once more. Realizing that the tin-foil machine was not an ideal type and could not come into common use, he determined to re-design it, and make it an instrument that could be handled by any one.
This meant the design and construction of an entirely different type of machine, and resulted in the kind of phonograph with which every one is familiar in these modern days. One of the chief differences was the use of a wax cylinder instead of tin-foil, and, instead of indenting with a pointed stylus, the record is cut into the wax with a tiny sapphire, the next hardest jewel to a diamond.
Into his improvements of the phonograph Mr. Edison has put an enormous amount of time and work. He has never lost interest, but has worked on it more or less through all the intervening years up to the present time. Even during recent years he has expended a prodigious amount of energy in improving the reproducer and other parts, spending night after night, and frequently all night, at the laboratory.
Inasmuch as great quantities of phonographs were sold, requiring millions of records, one of the difficulties to be overcome was to make large numbers of duplicates from an original record made by a singer, speaker, or band of musicians.
This difficulty will be perceived when it is stated that the record cut into the wax cylinder is hardly ever greater than one-thousandth of an inch deep, which is less than the thickness of a sheet of tissue paper, and in a single phonograph record there are many millions of sound-waves so recorded.
Through endless experiments of Edison and his working force, and with many ingenious inventions, however, these difficulties were overcome one by one.
It may be added that the phonograph was an invention so absolutely new that when Mr. Edison applied for his original patent, in 1877, the Patent Office could not find that any such attempt had ever before been made to record and reproduce speech or other sounds, and the patent was granted immediately. He has since taken out more than one hundred patents on improvements.
The original patent has long since expired, and many kinds of talking-machines are now made by others also, but they all operate on the identical principle which Edison was the first to discover and put into actual practice.
In these modern times an incandescent electric lamp is such an every-day affair as to be a familiar object even to a small child. But only a few years ago—a little over thirty—the man who proposed and invented it was derided in the newspapers, and called a madman and a dreamer.
If among Edison's numerous inventions there should be selected one or a class that might be considered the greatest, it seems to be universal opinion that the palm would be awarded to the incandescent lamp and hiscomplete systemfor the distribution of electric light, heat, and power. These inventions as a class, and what has sprung from them, have brought about most wonderful changes in the world.
The year 1877 was a busy one at Edison's laboratory at Menlo Park. He was engaged on the telephone, on acoustic electric transmission, sextuplex telegraphs, duplex telegraphs, miscellaneous carbon articles, and other things. He also commenced experimenting on the electric light.
Besides, as we have seen in the previous chapter, he invented the phonograph. The great interest and excitement caused by the latter invention took up nearly all of his time and attention for many months, and, indeed, up to July, 1878. He then took a vacation and went out to Wyoming with a party of astronomers to observe an eclipse of the sun and to make a test of his tasimeter.
He was absent about two months, coming home rested and refreshed. Mr. Edison says: "After my return from the trip to observe the eclipse of the sun I went with Professor Barker, professor of physics in the University of Pennsylvania, and Dr. Chandler, professor of chemistry in Columbia College, to see Mr. Wallace, a large manufacturer of brass in Ansonia, Connecticut. Wallace at this time was experimenting on series arc lighting. Just at that time I wanted to take up something new, and Professor Barker suggested that I go to work and see if I could subdivide the electric light so it could be got in small units like gas. This was not a new suggestion, because I had made a number of experiments on electric lighting a year before this. They had been laid aside for the phonograph. I determined to take up the search again and continue it. On my return home I started my usual course of collecting every kind of data about gas; bought all the transactions of the gas engineering societies, etc., all the back volumes of gas journals, etc. Having obtained all the data, and investigated gas-jet distribution in New York by actual observations, I made up my mind that the problem of the subdivision of the electric current could be solved and made commercial."
The problem which Edison had undertaken to solve was a gigantic one. The arc light was then known and in use to a very small extent, but the subdivision of the electric light—as it was then called—had not been accomplished. It had been the dream of scientists and inventors for a long time.
Innumerable trials and experiments had been made in America and Europe for many years, but without success. Although a great number of ingenious lamps had been made by the foremost inventors of the period, they were utterly useless as part of a scheme for a system of electric lighting. In fact, these efforts had been so unsuccessful that many of the leading scientists of the time, even as late as 1879, declared that the subdivision of the light was an impossibility.
The chief trouble was that the early experimenters did not conceive the idea of asystem, and worked only on a lamp. They all seemed to have the idea that an electric lamp was the main thing and that it should be of low resistance and should be operated on a current of very low voltage, or pressure. They, therefore experimented on lamps using short carbon rods or strips for burners, which required a large quantity of current.
Electric lighting with this kind of lamp was indeed a practical impossibility. The quantity of current required for a large number of them would have been prodigious, giving rise to tremendous problems on account of the heating effects. Besides, the most fatal objection was the cost of copper for conductors, which for a city section of about half a mile square would have cost not less than a hundred million dollars, on account of the enormous quantity of current that would be required.
Mr. Edison realized at the beginning that previous experimenters had failed because they had been following the wrong track. He knew that electric lighting could not be a success unless it could be sold to the public at a reasonable price and pay a profit to those who supplied it. With such lamps as had been proposed, requiring such an enormous outlay for copper, this would have been impossible. Besides, there would not have been enough copper in the world to supply conductors for one large city.
Edison did what he has so often done before and since. He turned about and went in the opposite direction. He reasoned that in order to develop a successful system of electric lighting the cost of conductors must come within very reasonable limits. To insure this, he must invent a lamp of comparatively high resistance, requiring only a small quantity of current, and with a burner having a small radiating surface.
Having the problem clearly in mind, Edison went to work in the fall of 1878 with that enthusiastic energy so characteristic of him. His earliest experiments were made with carbon as the burner for his lamp. In the previous year he had also experimented on this line, beginning with strips of carbon burned in the open air, and thenin vacuoby means of a hand-worked air-pump. These strips burned only a few minutes. On resuming his work in 1878 he again commenced with carbon, and made a very large number of trials, allin vacuo. Not only did he try ordinary strips of carbonized paper, but tissue-paper coated with tar and lampblack was rolled into thin sticks, like knitting-needles, carbonized and raised to the white heat of incandescencein vacuo.
He also tried hard carbon, wood carbon, and almost every conceivable variety of paper carbon in like manner. But with the best vacuum that he could then get by means of the ordinary hand-pump the carbons would last at the most only from ten to fifteen minutes in a state of incandescence.
It was evident to Edison that such results as these were not of commercial value. He feared that, after all, carbon was not the ideal substance he had thought it was for an incandescent lamp-burner. The lamp that he had in mind was one which should have a tough, hair-like filament for a light-giving body that could be maintained at a white heat for a thousand hours before breaking.
He therefore turned his line of experiments to wires made of refractory metals, such as platinum and iridium, and their alloys. These metals have very high fusing points, and while they would last longer than the carbon strips, they melted with a slight excess of current after they had been lighted but a short time.
Nevertheless, Edison continued to experiment along this line, making some improvements, until about April, 1879, he made an important discovery which led him to the first step toward the modern incandescent lamp. He discovered that if he introduced a piece of platinum wire into an all-glass globe, completely sealed and highly exhausted of air, and passed a current through the platinum wire while the vacuum was being made the wire would give a light equal to twenty-five candle-power without melting. Previously, the same length of wire would melt in the open air when giving a light equal to four candles.
He thus discovered that the passing of current through the platinum while the vacuum was being obtained would drive out occluded gases (i.e., gases mechanically held in or upon the metal). This was important and soon led to greater results.
Edison and his associates had been working night and day at the Menlo Park laboratory, and now that promising results were ahead their efforts went on with greater vigor than ever. Taking no account of the passage of time, with an utter disregard of meal-times, and with but scanty hours of sleep snatched reluctantly at odd periods, Edison labored on, and the laboratory was kept going without cessation.
Following up the progress he had made, Edison made improvement after improvement, especially in the line of high vacua, and about the beginning of October had so improved his pumps that he could produce a vacuum up to the one-millionth part of an atmosphere. It should be understood that the maintaining of such a high vacuum was only rendered possible by Edison's invention of a one-piece all-glass globe, hermetically sealed during its manufacture into a lamp.
In obtaining this perfection of vacuum apparatus Edison realized that he was drawing nearer to a solution of the problem. For many reasons, however, he was dissatisfied with platino-iridium filaments for burners, and went back to carbon, which from the first he had thought of as an ideal substance for a burner.
His next step proved that he was correct. On October 21, 1879, after many patient trials, he carbonized a piece of cotton sewing-thread bent into a loop or horseshoe form, and had it sealed into a glass globe from which he exhausted the air until a vacuum up to one-millionth of an atmosphere was produced. This lamp, when put on the circuit, lighted up brightly to incandescence and maintained its integrity for over forty hours, and lo! the practical incandescent lamp was born. The impossible, so called, had been attained; subdivision of the electric current was made practicable; the goal had been reached, and one of the greatest inventions of the century was completed.
Edison and his helpers stayed by the lamp during the whole forty hours watching it, some of the men making bets as to how long it would burn. It may well be imagined that there was great jubilation throughout the laboratory during those two days of delight and anxiety.
But now that the principle was established work was renewed with great fervor in making other lamps. A vast number of experiments were made with carbons made of paper, and the manufacture of lamps with these paper carbons was carried on continuously. A great number of these were made and put into actual use.
Edison was not satisfied, however. He wanted something better. He began to carbonize everything that he could lay hands on. In his laboratory note-books are innumerable jottings of the things that were carbonized and tried, such as tissue-paper, soft paper, all kinds of cardboards, drawing paper of all grades, paper saturated with tar, all kinds of threads, fish-line, threads rubbed with tarred lampblack, fine threads plaited together in strands, cotton soaked in boiling tar, lamp-wick, twine, tar and lampblack mixed with a proportion of lime, vulcanized fiber, celluloid, boxwood, cocoanut hair and shell, spruce, hickory, baywood, cedar, and maple shavings, rosewood, punk, cork, bagging, flax, and a host of other things.
He also extended his searches far into the realms of nature in the line of grasses, plants, canes, and similar products, and in these experiments at that time and later he carbonized, made into lamps, and tested no fewer than six thousand different species of vegetable growths.
At this time Edison was investigating everything with a microscope. One day he picked up a palm-leaf fan and examined the long strip of cane binding on its edge. He gave it to one of his assistants, telling him to cut it up into filaments, carbonize them, and put them into lamps.
These proved to be the best thus far obtained, and on further examination Edison decided that he had now found the best material so far tried, and a material entirely suitable for his lamps.
Within a very short time he sent a man off to China and Japan to search for bamboo, with instructions to keep on sending samples until the right one was found. This man did his work well, and among the species of bamboo he sent was one that was found satisfactory. Mr. Edison obtained a quantity of this and arranged with a farmer in Japan to grow it for him and to ship regular supplies. This was done for a number of years, and during that time millions of Edison lamps were regularly made from that particular species of Japanese bamboo.
Mr. Edison did not stop at this, however. He was continually in search of the best, and sent other men out to Cuba, Florida, and all through South America to hunt for something that might be superior to what he was using. Another man was sent on a trip around the world for the same purpose.
Some of these explorers met with striking adventures during their travels, and all of them sent vast quantities of bamboos, palms, and fibrous grasses to the laboratory for examination, but Edison never found any of them better for his purposes than the bamboo from Japan.
In this remarkable exploration of the world for such a material will be found an example of the thoroughness of Edison's methods. He is not satisfied to believe he has the best until he has proved it, and this search for the best bamboo was so thorough that it cost him altogether about one hundred thousand dollars.
In the meantime he was experimenting to manufacture an artificial filament that would be better than bamboo. He finally succeeded in his efforts, and brought out what is known as a "squirted" filament. This was made of a cellulose mixture and pressed out in the form of a thread through dies. This kind of filament has gradually superseded the bamboo in the manufacture of lamps.
We have been obliged to confine ourselves to a very brief outline history of the invention and development of the incandescent lamp. To tell the detailed story of the intense labors of the inventor and his staff of faithful workers would require a volume as large as the present one.
All that could be done in the space at our disposal was to try and give the reader a general idea of the clear thinking, logical reasoning, endless experimenting, hard work, and thoroughness of method of Edison in the creation of a new art.
In the history of the world's progress, Menlo Park, New Jersey, will ever be famous as the birthplace of the carbon transmitter, the phonograph, the incandescent lamp, the commercial dynamo, and the fundamental systems of distributing electric light, heat, and power.
In this list might also be included the electric railway, for while others had previously made some progress in this direction, it was in this historic spot that Edison did his pioneer work that advanced the art to a stage of practicability.
The name of Menlo Park will not have as striking a significance to the younger readers as to their elders whose recollections carry them back to the years between 1876 and 1886. During that period the place became invested with the glamor of romance by reason of the many startling and wonderful inventions coming out of it from time to time.
Edison worked there during these ten years. He had adopted Invention as a profession. As we have seen, he had always had a passion for a laboratory. Thus, from the little cellar at Port Huron, from the scant shelves in a baggage car, from the nooks and corners of dingy telegraph offices, and the grimy little shops in New York and Newark, he had come to the proud ownership of areallaboratory where he could wrestle with Nature for her secrets.
Here he could experiment to his heart's content, and invent on a bolder and larger scale than ever before. All the world knows that he did.
Menlo Park was the merest hamlet, located a few miles below Elizabeth. Besides the laboratory buildings, it had only a few houses, the best-looking of which Edison lived in. Two or three of the others were occupied by the families of members of his staff; in the others boarders were taken.
During the ten years that Edison occupied his laboratory there, life in Menlo Park could be summed up in one short word—work. Through the days and through the nights, year in and year out, for the most part, he and his associates labored on unceasingly, snatching only a few hours of sleep here and there when tired nature positively demanded it. Such a scene of concentrated and fruitful activity the world has probably never seen.
The laboratory buildings consisted of the laboratory proper, the library and office, a machine shop, carpenter shop, and some smaller buildings, and, later on, a wooden building, which was used for a short time as an incandescent lamp factory.
Here Edison worked through those busy years, surrounded by a band of chosen assistants, whose individual abilities and never-failing loyalty were of invaluable aid to him in accomplishing the purposes that he had in mind.
As to these associates, we quote Mr. Edison's own words from an autobiographical article in theElectrical Worldof March 5, 1904: "It is interesting to note that in addition to those mentioned above (Charles Batchelor and Francis R. Upton), I had around me other men who ever since have remained active in the field, such as Messrs. Francis Jahl, William J. Hammer, Martin Force, Ludwig K. Boehm, not forgetting that good friend and co-worker, the late John Kruesi. They found plenty to do in the various developments of the art, and as I now look back I sometimes wonder how we did so much in so short a time."
To this roll of honor may be added the names of a few others: The Carman brothers, Stockton L. Griffin, Dr. A. Haid, John F. Ott (still with Mr. Edison at Orange), John W. Lawson, Edward H. Johnson, Charles L. Clarke, William Holzer, James Hippie, Charles T. Hughes, Samuel D. Mott, Charles T. Mott, E. G. Acheson, Dr. E. L. Nichols, J. H. Vail, W. S. Andrews, and Messrs. Worth, Crosby, Herrick, Hill, Isaacs, Logan, and Swanson.
To these should be added the name of Mr. Samuel Insull, who, in 1881, became Mr. Edison's private secretary, and who for many years afterward managed all his business affairs.
Mr. Insull's position as secretary in the Menlo Park days was not a "soft snap," as his own words will show. He says: "I never attempted to systematize Edison's business life. Edison's whole method of work would upset the system of any office. He was just as likely to be at work in his laboratory at midnight as midday. He cared not for the hours of the day or the days of the week. If he was exhausted he might more likely be asleep in the middle of the day than in the middle of the night, as most of his work in the way of invention was done at night. I used to run his office on as close business methods as my experience admitted, and I would get at him whenever it suited his convenience. Sometimes he would not go over his mail for days at a time, but other times he would go regularly to his office in the morning. At other times my engagements used to be with him to go over his business affairs at Menlo Park at night, if I was occupied in New York during the day. In fact, as a matter of convenience I used more often to get at him at night as it left my days free to transact his affairs, and enabled me, probably at a midnight luncheon, to get a few minutes of his time to look over his correspondence and get his directions as to what I should do in some particular negotiation or matter of finance. While it was a matter of suiting Edison's convenience as to when I should transact business with him, it also suited my own ideas, as it enabled me after getting through my business with him to enjoy the privilege of watching him at his work, and to learn something about the technical side of matters. Whatever knowledge I may have of the electric light and power industry I feel I owe it to the tuition of Edison. He was about the most willing tutor, and I must confess that he had to be a patient one."
It must not be supposed that the hard work of these times made life a burden to the small family of laborers associated with Edison. On the contrary, they were a cheerful, happy lot of men, always ready to brighten up their strenuous life by the enjoyment of anything of a humorous nature that came along.
Often during the long, weary nights of experimenting Edison would call a halt for refreshments, which he had ordered always to be sent in at midnight when night work was in progress. Everything would be dropped, all present would join in the meal, and the last good story or joke would pass around.
Mr. Jehl has written some recollections of this period, in which he says: "Our lunch always ended with a cigar, and I may mention here that although Edison was never fastidious in eating, he always relished a good cigar, and seemed to find in it consolation and solace.... It often happened that while we were enjoying the cigars after our midnight repast, one of the boys would start up a tune on the organ and we would sing together, or one of the others would give a solo. Another of the boys had a voice that sounded like something between the ring of an old tomato-can and a pewter jug. He had one song that he would sing while we roared with laughter. He was also great in imitating the tin-foil phonograph. When Boehm was in good humor he would play his zither now and then, and amuse us by singing pretty German songs. On many of these occasions the laboratory was the rendezvous of jolly and convivial visitors, mostly old friends and acquaintances of Mr. Edison. Some of the office employees would also drop in once in a while, and, as every one present was always welcome to partake of the midnight meal, we all enjoyed these gatherings. After a while, when we were ready to resume work, our visitors would intimate that they were going home to bed, but we fellows could stay up and work, and they would depart, generally singing some song like 'Good-night, Ladies!'... It often happened that when Edison had been working up to three or four o'clock in the morning he would lie down on one of the laboratory tables, and with nothing but a couple of books for a pillow, would fall into a sound sleep. He said it did him more good than being in a soft bed, which spoils a man. Some of the laboratory assistants could be seen now and then sleeping on a table in the early morning hours. If their snoring became objectionable to those still at work, the 'calmer' was applied. This machine consisted of a Babbitt's soap-box without a cover. Upon it was mounted a broad ratchet-wheel with a crank, while into the teeth of the wheel there played a stout, elastic slab of wood. The box would be placed on the table where the snorer was sleeping and the crank turned rapidly. The racket thus produced was something terrible, and the sleeper would jump up as though a typhoon had struck the laboratory. The irrepressible spirit of humor in the old days, although somewhat strenuous at times, caused many a moment of hilarity which seemed to refresh the boys, and enabled them to work with renewed vigor after its manifestation."
The "boys" were ever ready for a joke on one of their number. Mr. Mackenzie, who taught Edison telegraphy, spent a great deal of time at the laboratory. He had a bushy red beard, and was persuaded to give a few hairs to be carbonized and used for filaments in experimental lamps. When the lamps were lighted the boys claimed that their brightness was due to the rich color of the hairs.
The history of the busy years at Menlo Park would make a long story if told in full, but only a hint can be given here of the gradual development of many important inventions. These include the innumerable experiments on the lamp, on different kinds and weights of iron for field magnets and armatures, on magnetism, on windings and connections for field magnets and armatures, on distribution circuits, control, and regulation, and so on through a long list.
All these things were new. There was nothing in the books to serve as a guide in solving these new problems, but Edison patiently worked them out, one by one, until a complete system was the result of his labors.
Menlo Park was historic in one other particular. It was the very first place in the world to see incandescent electric lighting from a central station.
The newspapers had been so full of the wonderful invention that there was a great demand to see the new light. Edison decided to give a public exhibition, and for this purpose put up over four hundred lights in the streets and houses of Menlo Park, all connected to underground conductors which ran to the dynamos in one of the shop buildings.
On New Year's Eve, 1879, the Pennsylvania Railroad ran special trains, and over three thousand people availed themselves of the opportunity to witness the demonstration. It was a great success, and gave rise to a wide public interest.
Edison's laboratory at Menlo Park had never suffered for lack of visitors, but now it became a center of attraction for scientific and business men from all parts of the world. Pages of this book could be filled with the names of well-known visitors at this period, but it would be of no practical use to give them; besides we must now pass on to the time when the light was introduced to the world.
The close of the last two chapters found us attending the birth of an art that was then absolutely and entirely new—the art of electric lighting by incandescent lamps. It will now be interesting to take a brief glance at the way in which it was introduced to the world.
Edison invented not only a lamp and a dynamo, but a completesystemof distributing electric light, heat, and power from central stations. This included a properly devised network of conductors fed with electricity from several directions and capable of being tapped to supply current to each building; a lamp that would be cheap, lasting, take little current, be easy to handle, and each to be independent of every other lamp; means for measuring electricity by meter; means for regulating the current so that every lamp, whether near to or far away from the station, would give an equal light; the designing of new and efficient dynamos, with means for connecting and disconnecting and for regulating and equalizing their loads; the providing of devices that would prevent fires from excessive current, and the providing of switches, lamp-holders, fixtures, and the like.
This was a large program to fill, for it was all new, and there was nothing in the world from which to draw ideas, but Edison carried out his scheme in full, and much more besides. By the end of 1880 he was ready to launch his electric light system for commercial use, and the Edison Electric Light Company, that had been organized for the purpose, rented a mansion at No. 65 Fifth Avenue, New York, to be used for offices. Edison now moved some of his Menlo Park staff into that city to pursue the work.
Right at the very beginning a most serious difficulty was met with. None of the appliances necessary for use in the lighting system could be purchased anywhere in the world.
They were all new and novel—dynamos, switchboards, regulators, pressure and current indicators, incandescent lamps, sockets, small switches, meters, fixtures, underground conductors, junction boxes, service boxes, manhole boxes, connectors, and even specially made wire. Not one of these things was in existence; and no outsider knew enough about such devices to make them on order, except the wire.
Edison himself solved the difficulty by raising some money and establishing several manufacturing shops in which these articles could be made. The first of all was a small factory at Menlo Park to make the lamps, Mr. Upton taking charge of that branch.
For making the dynamos he secured a large works on Goerck Street, New York, and gave its management to Mr. Batchelor. For the underground conductors and their parts a building on Washington Street was rented and the work done under the superintendence of Mr. Kruesi. In still another factory building there were made the smaller appliances, such as sockets, switches, fixtures, meters, safety fuses and other details. This latter plant was at first owned by Mr. Sigmund Bergmann, who had worked with Edison on telephones and phonographs, but later Mr. Edison and E. H. Johnson became partners.
Still another difficulty presented itself. There were no men who knew how to do wiring for electric lights, except those who had been with Edison at Menlo Park. This problem was solved by opening a night-school at No. 65 Fifth Avenue in which a large number of men were educated and trained for the work by Edison's associates. Many of these men have since become very prominent in electrical circles.
Thus, in planning these matters, and in guiding the operations in these four shops in New York, and with all the work he was doing on new experiments and inventions there and at Menlo Park, and in making preparations for the first central station in New York City, Edison was a prodigiously busy man. He worked incessantly, and it is safe to say that he did not average more than four hours' sleep a day.
He was the center and the guiding spirit of those intensely busy times. The aid of his faithful associates was invaluable in the building up of the business, but he was the great central storehouse of ideas, and it is owing to his undaunted courage, energy, perseverance, knowledge and foresight, that the foundations of so great an art have been so well laid.
As has been well said by Major S. B. Eaton, who was president and general manager of the Edison Electric Light Company in its earliest years: "In looking back on those days and scrutinizing them through the years, I am impressed by the greatness, the solitary greatness, I may say, of Mr. Edison. We all felt then that we were of importance, and that our contribution of effort and zeal was vital. I can see now, however, that the best of us was nothing but the fly on the wheel. Suppose anything had happened to Edison? All would have been chaos and ruin. To him, therefore, be the glory, if not the profit."
Early in 1881 comparatively few people had seen the incandescent light. In order to make the public familiar with it, the Edison company equipped its office building with fixtures and lamps, the latter being lighted by current from a dynamo in the cellar. In the evenings the house was thrown open to visitors until ten or eleven o'clock. Thousands of people flocked to see the new light, which in those days was regarded as wonderful and mysterious, for while the lamps gave a soft, steady illumination, there was no open flame, practically no heat, no danger of fire, and no vitiation of air. For the most part of four years the writer spent his evenings receiving these visitors if no important business was in progress at the moment.
Mr. Edison and his shops had scarcely time to get well on their feet before a rush of business set in. How this business rapidly developed and grew until it became of very great magnitude is a matter of history, which we shall not attempt to relate here.
Some idea of this wonderful development, as it has gone on through the years that have passed since 1880, may be formed when it is stated that at this time there are more than one hundred millions of incandescent lamps in daily use in the United States alone. Every one of these lamps and the fundamental principles upon which they are operated rest upon the foundations which Edison laid so well.
One of Mr. Edison's interesting stories of the early days relates to the making of the lamps. He says:
"When we first started the electric light we had to have a factory for manufacturing lamps. As the Edison light company did not seem disposed to go into manufacturing, we started a small lamp factory at Menlo Park with what money I could raise from my other inventions and royalties and some assistance. The lamps at that time were costing about one dollar and twenty-five cents each to make, so I said to the company: 'If you will give me a contract during the life of the patents I will make all the lamps required by the company and deliver them for forty cents.' The company jumped at the chance of this offer, and a contract was drawn up. We then bought at a receiver's sale at Harrison, New Jersey, a very large brick factory building which had been used as an oil-cloth works. We got it at a great bargain, and only paid a small sum down, and the balance on mortgage. We moved the lamp works from Menlo Park to Harrison. The first year the lamps cost us about one dollar and ten cents each. We sold them for forty cents; but there were only about twenty or thirty thousand of them. The next year they cost us about seventy cents, and we sold them for forty. There were a good many, and we lost more money the second year than the first. The third year I succeeded in getting up machinery and in changing the processes, until it got down so that they cost somewhere around fifty cents. I still sold them for forty cents, and lost more money that year than any other, because the sales were increasing rapidly. The fourth year I got it down to thirty-seven cents, and I made all the money in one year that I had lost previously. I finally got it down to twenty-two cents, and sold them for forty cents; and they were made by the million. Whereupon the Wall Street people thought it was a very lucrative business, so they concluded they would like to have it, and bought us out.
"When we formed the works at Harrison we divided the interests into one hundred shares or parts at one hundred dollars par. One of the boys was hard up after a time, and sold two shares to Bob Cutting. Up to that time we had never paid anything, but we got around to the point where the board declared a dividend every Saturday night. We had never declared a dividend when Cutting bought his shares, and after getting his dividends for three weeks in succession he called up on the telephone and wanted to know what kind of a concern this was that paid a weekly dividend. The works sold for $1,085,000."
We have been obliged to confine ourselves to a very brief and general description of the beginnings of the art of electric lighting, but this chapter would not be complete without reference to Edison's design and construction of the greatest dynamo that had ever been made up to that time.
The earliest dynamos he made would furnish current only for sixty lamps of sixteen candle-power each. These machines were belted up to an engine or countershaft. He realized that much larger dynamos would be needed for central stations, and in 1880 constructed one in Menlo Park, but it was not entirely successful.
In the spring of 1881, however, he designed a still larger one, to be connected direct to its own engine and operated without belting. Its capacity was to be twelve hundred lamps, instead of sixty.
At that time such a project was not dreamed of outside the Edison laboratory, and once more he was the subject of much ridicule and criticism by those who were considered as experts. They said the thing was impossible and absolutely impracticable.
Such opinions, however, have never caused a moment's hesitation to Edison when he has made up his mind that a thing can be done. He calmly went ahead with his plans, and although he found many difficulties, he overcame them all. He worked the shops night and day, until he had built this great machine and operated it successfully.
The dynamo was finished in the summer of 1881. At that time there was in progress an international Electrical Exposition in Paris, at which Edison was exhibiting his system of electric lighting. He had promised to send this great dynamo over to Paris.
When the dynamo was finished and tested there were only four hours to take it and the engine apart and get all the parts on board the steamer. Edison had foreseen all this, and had arranged to have sixty men get to work all at once to take it apart. Each man had written instructions just what to do, and when the machine was stopped every man did his own particular work and the job was quickly accomplished.
Arrangements had been made with the police for rapid passage through the streets from the shops to the steamship. The trucks made quick time of it, being preceded by a wagon with a clanging bell. Street traffic was held up for them, just as it is for engines and hose-carts going to a fire. The dynamo and engine got safely down to the dock without delay and were loaded on the steamer an hour before she sailed.
This dynamo and engine weighed twenty-seven tons, and was then, and for a long time after, the eighth wonder of the scientific world. Its arrival and installation in Paris were eagerly watched by the most famous scientists and electricians in Europe.
From the beginning of his experiments on the electric light Edison had one idea ever in mind, and that was to develop a system of lighting cities from central stations. His plan was to supply electric light and power in much the same way that gas is furnished.
He never forsook this idea for a moment. Indeed, it formed the basis of all his plans, although the scientific experts of the time predicted utter failure. While the experiments were going on at Menlo Park he had Mr. Upton and others at work making calculations and plans for city systems.
Soon after he had invented the incandescent lamp he began to take definite steps toward preparing for the first central station in the city of New York. After some consideration, he decided upon the district included between Wall, Nassau, Spruce and Ferry Streets, Peck Slip and the East River, covering nearly a square mile in extent.
He sent into this district a number of men, who visited every building, counted every gas-jet and found out how many hours per day or night they were burned.
These men also ascertained the number of business houses using power and how much they consumed. All this information was marked in colored inks on large maps, so that Edison could study the question with all the details before him.
All this work had taken several months, but, with this information to guide him, the main conductors to be laid in the streets of this district were figured, block by block, and the results were marked upon the maps. It was found, however, that the quantity of copper required for these conductors would be exceedingly large and costly, and, if ever, Edison was somewhat dismayed.
This difficulty only spurred him on to still greater effort. Before long he solved the problem by inventing the "feeder and main" system, for which he signed an application for patent on August 4, 1880.
By this invention he saved seven-eighths of the amount of copper previously required. So the main conductors were figured again, at only one-eighth the size they were before, and the results were marked upon enormous new maps which were now prepared for the actual installation.
It should be remembered that from the very start Edison had determined that his conductors should be placed underground. He knew that this was the only method for permanent and satisfactory service to the public.
Our young readers can scarcely imagine the condition of New York streets at that time. They were filled with lines of ugly wooden poles carrying great masses of telegraph, telephone, stock ticker, burglar alarm and other wires, in all conditions of sag and decay. The introduction of the arc-lamp added another series of wires which with their high potentials carried a menace to life. Edison was the first to put conductors underground, and the wisdom of so doing became so clear that a few years later laws were made compelling others to do likewise.
But to return to our story. Just before Christmas in 1880 the Edison Electric Illuminating Company of New York was organized, and a license was issued to it for the use of the Edison patents on Manhattan Island.
The work for the new station now commenced in real earnest. A double building at 255 and 257 Pearl Street was purchased, and the inside of one half was taken out and a strong steel structure was erected inside the walls.
Work on the maps and plans for the underground network of conductors was continued at Menlo Park. Mr. Edison started his factories for making dynamos, lamps, underground conductors, sockets, switches, meters, and other details. Thus, the wheels of industry were humming merrily in preparation for the installation of the system. Every detail received Edison's personal care and consideration. He had plenty of competent men, but he deemed nothing too small or insignificant for his attention in this important undertaking.
In the fall of 1881 the laying of the underground conductors was begun and pushed forward with frantic energy. Here again Edison left nothing to chance. Although he had a thousand things to occupy his mind he also superintended this work. He did not stand around and give orders, but worked with the men in the trenches day and night helping to lay tubes, filling up junction boxes, and taking part in all the infinite detail.
He would work till he felt the need of a little rest. Then he would go off to the station building in Pearl Street, throw an overcoat on a pile of iron tubes, lie down and sleep a few hours, rising to resume work with the first gang.
It is worth pausing just a moment to glance at this man taking a fitful rest on a pile of iron pipe in a dingy building. His name is on the tip of the world's tongue. Distinguished scientists from every part of Europe seek him eagerly. He has just been decorated and awarded high honors by the French government. He is the inventor of wonderful new apparatus and the exploiter of novel and successful arts. The magic of his achievements and the rumors of what is being done have caused a wild drop in gas securities and a sensational rise in his own electric-light stock from one hundred dollars to thirty-five hundred a share. Yet these things do not at all affect his slumber or his democratic simplicity, for in that, as in everything else, he is attending strictly to business, "doing the thing that is next to him."
The laying of the underground conductors was interrupted by frost in the winter of 1881, but in the following spring the work was renewed with great energy until there had been laid over eighty thousand feet. In the mean time the buildings of the district were being wired for lamps, and the machine-works had been busy on the building of three of the "Jumbo" dynamos for the station. These were larger than the great dynamo that had been sent to Paris.
These three dynamos were installed in the station, and the other parts of the system were completed. A bank of one thousand lamps was placed in one of the buildings; and in the summer a whole month was spent in making tests of the working of the system, using this bank of lamps instead of sending current out to customers' premises. Edison and his assistants made the station their home during this busy month. They even slept there on cots that he had sent to the station for this purpose.
The system tested out satisfactorily, and finally, on September 4, 1882, at three o'clock in the afternoon, the station was started by sending out current from one of the big dynamos through the conductors laid in the streets, and electric light was supplied for the first time to a number of customers in the district.