Part 16

A little later, when Edison was employed as operator in the railroad office at Indianapolis, he practiced receiving newspaper reports in his spare hours at night. He and a friend named Parmley would take the place of the regular man, who was glad to have them do it. “I would sit down,” said Edison, “for ten minutes, and ‘take’ as much as I could from the instrument, carrying the rest in my head. Then while I wrote out, Parmley would serve his turn at ‘taking,’ and so on. This worked well until they put a new man on at the Cincinnati end. He was one of the quickest despatchers in the business, and we soon found it was hopeless for us to try to keep up with him. Then it was that I worked out my first invention, and necessity was certainly the mother of it.

“I got two old Morse registers and arranged them in such a way that by running a strip of paper through them the dots and dashes were recorded on it by the first instrument as fast as they were delivered from the Cincinnati end, and were transmitted to us through the other instrument at any desired rate of speed. They would come in on one instrument at the rate of forty words a minute, and would be ground out of our instrument at the rate of twenty-five. Then weren’t we proud! Our copy used to be so clean and beautiful that we hung it up on exhibition; and our manager used to come and gaze at it silently with a puzzled expression. He could not understand it, neither could any of the other operators; for we used to hide my impromptu automatic recorder when our toil was over. But the crash came when there was a big night’s work--a presidential vote, I think it was--and copy kept pouring in at the top rate of speed until we fell an hour and a half or two hours behind. The newspapers sent in frantic complaints, an investigation was made, and our little scheme was discovered. We couldn’t use it any more.”

His fortunes rose and fell, for, although he was now becoming a very expert operator, taking messages with greater and greater speed, he would continue to stray into new fields of experiment. When he started to work in the Western Union office in Memphis, which was soon after the end of the Civil War, he found that all messages that were sent from New Orleans to New York had to be received at Memphis, sent on from there to Louisville, taken again, and so forwarded by half a dozen relays to New York. Many errors might creep in by such a system. To cure this he devised an automatic repeater, which could be attached to the line at Memphis, and would of its own accord send the message on. In this way the signals could go directly from New Orleans to New York. The device worked, and was highly praised in the local newspapers. But it happened that the manager of the office had a relative who was just completing a similar instrument, and Edison had forestalled him. Consequently he found himself discharged. He got a railroad pass as far as Decatur, and walked a hundred and fifty miles from there to Nashville. So by alternate riding and walking he finally reached Louisville. A little later he was offered a place in the Boston office.

He had plenty of nerve, and was not at all put out at the amusement of the other men when he walked into the Boston office, clad in an old and shapeless linen duster. “Here I am,” he announced to the superintendent. “And who are you?” he was asked. “Tom Edison. I was told to report here.”

The superintendent sent him to the operating-room. Shortly after a New York telegrapher, famed for his speed, called up. Every one else was busy, and Edison was told to take his message. He sat down, and for four and a half hours wrote the messages, numbering the pages and throwing them on the floor for the office boy to gather up. As time went on the messages came with such lightning speed that the whole force gathered about to see the new man work. They had never seen such quickness. At the end of the last message came the words, “Who the devil are you?” “Tom Edison,” the operator ticked back. “You are the first man in the country,” wired the man in New York, “that could ever take me at my fastest, and the only one who could ever sit at the other end of my wire for more than two hours and a half. I’m proud to know you.”

This story may be legendary, but it is known to be a fact that Edison was at this time the fastest operator in the employ of the Western Union, and that he could take the messages sent him with a careless ease which amounted almost to indifference. He had also cultivated an unusually clear handwriting, which was of great help in writing out the messages.

As soon as he was settled at the Boston office he opened a small workshop, where he might try to complete some of the many devices he had in mind. He took out his first patent in 1868, when he was twenty-one years old, and it was obtained for what he called an electrical vote recorder. This was intended for use in Congress and the State Legislatures, and to take the place of the slow process of calling the roll on any vote. It was worked somewhat on the plan of the hotel indicator. The voter, sitting at his desk, would press one button if he wanted to vote “aye,” and another if he wanted to vote “no.” His vote was then recorded on a dial by the Speaker’s desk, and as soon as each member had pressed one or the other button the total votes on each side could be known. The machine worked perfectly, and Edison took it to Washington in high hopes of having it adopted by Congress. The chairman to whom he was referred examined it carefully. Then he said, “Young man, it works all right and couldn’t be better. With an instrument like that it would be difficult to monkey with the vote if you wanted to. But it won’t do. In fact, it’s the last thing on earth that we want here. Filibustering and delay in the counting of the votes are often the only means we have of defeating bad legislation. So, though I admire your genius and the spirit which prompted you to invent so excellent a machine, we shan’t require it here. Take the thing away.”

“Of course I was very sorry,” said Edison, in speaking of this interview later, “for I had banked on that machine bringing me in money. But it was a lesson to me. There and then I made a vow that I would never invent anything which was not wanted, or which was not necessary to the community at large. And so far I believe I have kept that vow.”

It was very evident there was a keen-witted man at work in the Boston office. The operators there had been much annoyed by an army of cockroaches that used to march across the table where they put their lunches and make a raid on the sandwiches and pies. One day Edison appeared with some tin-foil and four or five yards of fine wire. He unrolled the tin-foil, and, cutting two narrow strips from the long sheet, he stretched them around the table, keeping them near together, but not touching, and fastening them with small tacks. Then he connected the ribbons of foil with two batteries.

The leaders of the cockroach army arrived. The advance guard got his fore-creepers over the first ribbon safely, but as soon as they touched the parallel ribbon over he fell. In a very short time the invading army had met its Waterloo, and the lunches were safe from any further attack.

At another time the tin dipper that hung by the tank of drinking-water temporarily disappeared. When it was returned Edison put up a sign, reading, “Please return this dipper.” He also connected the nail on which the dipper hung with a wire attached to an electric battery. After that the dipper stayed in its place under penalty of a wrenched arm for moving it without first disconnecting the battery.

Edison had now determined to become an inventor, and as soon as he was able gave up his position in the Boston telegraph office, where his routine work took too much of his time, and went to New York to look for other opportunities. It happened that one day soon after his arrival he was walking through Wall Street and was attracted to the office of the Law Gold Indicator. The indicators or stock-tickers of this company were a new device, and were distributed through most of the large brokerage houses of the city. On the morning when Edison casually looked in, the machines had stopped work, no one could find out what was the matter, and the brokers were much disturbed. Edison watched Mr. Law and his workmen searching for the trouble. Then he said that he thought he could fix the machines. Mr. Law told him to try. He removed a loose contact spring that had fallen between the wheels, and immediately the tickers began to work again. The other workmen looked foolish, and Mr. Law asked the newcomer to step into his private office. At the end of the interview the owner had offered Edison the position of manager at a salary of three hundred dollars a month, and Edison had accepted.

He determined to improve this stock-indicator, and set to work at once. Soon he had evolved a number of important additions. The president of the company sent for him and asked how much he would take for these improvements. The inventor said that he would leave that to the president. Forty thousand dollars was named and accepted. Edison opened a bank account, and gave more time to working in his own laboratory. He had got well started up the rungs of the ladder he planned to climb.

His work lay along the lines of the telegraph, and he was anxious to win the support of the Western Union for his new ideas. His chance came when there was a breakdown of the lines between New York and Albany. He went to the Western Union president, who had already heard of him, and said, “If I locate this trouble within two or three hours, will you take up my inventions and give them honest consideration?” The president answered, “I’ll consider your inventions if you get us out of this fix within two days.” Edison rushed forthwith to the main office. There he called up Pittsburg and asked for their best operator. When he had him he told him to call up the best man at Albany, and get him to telegraph down the line to New York as far as he could, and report back to him. Inside of an hour he received the message, “I can telegraph all right down to within two miles of Poughkeepsie, and there is trouble with the wire there.” Edison went back to the president and told him that if he would send a repair train to Poughkeepsie they would find a break two miles the other side of the city and could have it repaired that afternoon. They followed his directions, and communication was restored before night. After that the Western Union officials gave the most careful consideration to every new invention that Edison brought them.

As soon as he had money in bank Edison carried out a plan he had long had in mind. He gave up his workshop in New York and opened a factory and experimenting shop in Newark, New Jersey, where he would have plenty of room for himself and his assistants. He began by manufacturing his improved “stock-tickers,” and he met with very considerable success. But he felt that manufacturing was not his forte. He said of this venture later, “I was a poor manufacturer, because I could not let well enough alone. My first impulse upon taking any apparatus into my hand, from an egg-beater to an electric motor, is to seek a way of improving it. Therefore, as soon as I have finished a machine I am anxious to take it apart again in order to make an experiment. That is a costly mania for a manufacturer.”

In his Newark shop Edison now turned his attention to improvements on the telegraph. His first important invention was the duplex, by which two messages could be sent over the same wire in opposite directions at the same time without any confusion or obstruction to each other. This doubled the capacity of the single wire. Later he decided to carry this system farther, and perfected the quadruplex device. By this two messages could be sent simultaneously in each direction, and two sending and two receiving operators were employed at each end of a single wire. The principle involved was that of working with two electric currents that differ from each other in strength or nature, and which only affect receiving instruments specially adapted to take such currents, and no others. This invention changed a hundred thousand miles of wire into four hundred thousand, and saved the Western Union untold millions of dollars which would otherwise have had to be expended for new wires and repairs to the old ones.

Along somewhat similar lines Edison perfected an automatic telegraph, an harmonic multiplex telegraph, and an autographic telegraph. The harmonic multiplex used tuning-forks to separate the several different messages sent at the same time, and the autographic telegraph allowed of the transmission of an exact reproduction of a message written by the sender in one place and received in another. And in addition to all these leading inventions he was continually improving on the main system, and his improvements were rapidly bought and taken over by the Western Union Company.

In almost as many diverse ways Edison improved upon the telephone. He had left his factory in Newark in charge of a capable superintendent, and moved his own laboratories to Menlo Park, a quiet place about twenty-five miles from Newark. His striking discoveries soon earned for him the nickname of “The Wizard of Menlo Park.” Here he experimented with the new apparatus known as the telephone. He said of his own connection with it, “When I struck the telephone business the Bell people had no transmitter, but were talking into the magneto receiver. You never heard such a noise and buzzing as there was in that old machine! I went to work and monkeyed around, and finally struck the notion of the lampblack button. The Western Union Telegraph Company thought this was a first-rate scheme, and bought the thing out, but afterward they consolidated, and I quit the telephone business.” As a matter of fact Edison has done a great deal of other work besides inventing his carbon transmitter in the telephone field, and the Patent Office is well stocked with applications he has sent them for receivers and transmitters of different designs.

Edison has himself told of the main incidents in his perfection of the electric light. In the _Electrical Review_ he said, “In 1878 I went down to see Professor Barker, at Philadelphia, and he showed me an arc lamp--the first I had seen. Then a little later I saw another--I think it was one of Brush’s make--and the whole outfit, engine, dynamo, and one or two lamps, was traveling around the country with a circus. At that time Wallace and Moses G. Farmer had succeeded in getting ten or fifteen lamps to burn together in a series, which was considered a very wonderful thing. It happened that at the time I was more or less at leisure, because I had just finished working on the carbon-button telephone, and this electric-light idea took possession of me. It was easy to see what the thing needed: it wanted to be subdivided. The light was too bright and too big. What we wished for was little lights, and a distribution of them to people’s houses in a manner similar to gas. Grovernor P. Lowry thought that perhaps I could succeed in solving the problem, and he raised a little money and formed the Edison Electric Light Company. The way we worked was that I got a certain sum of money a week and employed a certain number of men, and we went ahead to see what we could do.

“We soon saw that the subdivision never could be accomplished unless each light was independent of every other. Now it was plain enough that they could not burn in series. Hence they must burn in multiple arc. It was with this conviction that I started. I was fired with the idea of the incandescent lamp as opposed to the arc lamp, so I went to work and got some very fine platinum wire drawn. Experiment with this, however, resulted in failure, and then we tried mixing in with the platinum about ten per cent. of iridium, but we could not force that high enough without melting it. After that came a lot of experimenting--covering the wire with oxide of cerium and a number of other things.

“Then I got a great idea. I took a cylinder of zirconia and wound about a hundred feet of the fine platinum wire on it coated with magnesia from the syrupy acetate. What I was after was getting a high-resistance lamp, and I made one that way that worked up to forty ohms. But the oxide developed the phenomena now familiar to electricians, and the lamp short-circuited itself. After that we went fishing around and trying all sorts of shapes and things to make a filament that would stand. We tried silicon and boron, and a lot of things that I have forgotten now. The funny part of it was that I never thought in those days that a carbon filament would answer, because a fine hair of carbon was so sensitive to oxidation. Finally, I thought I would try it because we had got very high vacua and good conditions for it.

“Well, we sent out and bought some cotton thread, carbonized it, and made the first filament. We had already managed to get pretty high vacua, and we thought, maybe, the filament would be stable. We built the lamp and turned on the current. It lit up, and in the first few breathless minutes we measured its resistance quickly and found it was 275 ohms--all we wanted. Then we sat down and looked at that lamp. We wanted to see how long it would burn. The problem was solved--if the filament would last. The day was--let me see--October 21, 1879. We sat and looked, and the lamp continued to burn, and the longer it burned the more fascinated we were. None of us could go to bed, and there was no sleep for any of us for forty hours. We sat and just watched it with anxiety growing into elation. It lasted about forty-five hours, and then I said, If it will burn that number of hours now, I know I can make it burn a hundred.’ We saw that carbon was what we wanted, and the next question was what kind of carbon. I began to try various things, and finally I carbonized a strip of bamboo from a Japanese fan, and saw that I was on the right track. But we had a rare hunt finding the real thing. I sent a schoolmaster to Sumatra and another fellow up the Amazon, while William H. Moore, one of my associates, went to Japan and got what we wanted there. We made a contract with an old Jap to supply us with the proper fibre, and that man went to work and cultivated and cross-fertilized bamboo until he got exactly the quality we required.”

This is the inventor’s own statement, but it gives a very meagre notion of the many months’ experimenting in his workshop while he hunted for a suitable filament for his electric light.

As he said, after he had first seen the Brush light, and studied it, he decided that the main problem was one of distribution, and thereupon considered whether he should use the incandescent or the voltaic arc in the system he was planning. At last he decided in favor of the incandescent light.

Then began the long months of testing platinum wire. He wanted to find some way of preventing this hardest of all metals from melting when the full force of the electric current was turned into it. He worked out several devices to keep the platinum from fusing, an automatic lever to regulate the electric current when the platinum was near the melting-point, and a diaphragm with the same object; but all of them had to be discarded. Although he was still searching for the right clue he seems to have had no doubt of his final success. He said at this time, “There is no difficulty about dividing up the current and using small quantities at different points. The trouble is in finding a candle that will give a pleasant light, not too intense, which can be turned off and on as easily as gas. Such a candle cannot be made from carbon points, which waste away, and must be regulated constantly while they do last. Some composition must be discovered which will be luminous when charged with electricity and that will not wear away. Platinum wire gives a good light when a certain quantity of electricity is passed through it. If the current is made too strong, however, the wire will melt. I want to get something better.”

It was generally known that Edison was working along this line. An English paper, commenting on the matter, said, “The weak point of the lamp is this, that in order to be luminous, platinum must be heated almost to the point of melting. With a slight increase in the current, the lamp melts in the twinkling of an eye, and in practice the regulator is found to short-circuit the current too late to prevent the damage. It is this difficulty which must be overcome. Can it be done?”

After long study Edison concluded that pure platinum was not suited to successful electric lighting. Then he incorporated with it another material of a non-conducting nature, with the result that when the electric current was turned on one material became incandescent and the other luminous. This gave a clear, but not a permanent, light. He tried many different combinations, and experimented month after month, but none of his trials produced the result he wanted, and at last he concluded that he was on the wrong track, and that neither platinum nor any other metal would give the right light.

There is something very dramatic about his real discovery. He was sitting in his laboratory one evening, when his right hand happened to touch a small pile of lampblack and tar that his assistants had been using in working on a telephone transmitter. He picked up a little of it, and began to roll it between his finger and thumb. He was thinking of other things, and he rolled the mixture absent-mindedly for some time, until he had formed a thin thread that looked something like a piece of wire. Glancing at it, he fell to wondering how it would serve as a filament for his light. It was carbon, and might be able to stand a stronger current than platinum. He rolled some more of the mixture, and decided to try it.

His experiments had already resulted in the production of an almost absolute vacuum, only one-millionth part of an atmosphere being left in the tube. Such a vacuum had never been obtained before. With his assistant, Charles Bachelor, he put a thread of the lampblack and tar in a bulb, exhausted the air, and turned on the current. There was an intense glow of light; but it did not last, the carbon soon burned out. Therefore he started to study the reason why the carbon had failed to withstand the electric current. His conclusion was that it was impossible to get the air out of the lampblack. Besides that the thread became so brittle that the slightest shock to the lamp broke it. But he felt certain now that a carbon filament, made of something other than tar and lampblack, was what he wanted.