ELECTRIC LIGHT AND THE PHONOGRAPH
Our Debt to Mr. EdisonóA Miracle of PatienceóThe Difference between Discovery and InventionóThe Making of the First Phonograph.
THERE is an advertisement which runs: "When you see a pillar box think of so-and-soís pen." In similar fashion one might be tempted to write: "When you see an electric lamp think of Edison."
Yet Edison was not the inventor of the electric light, for lights produced by electricity were made more than a quarter of a century before that great man was born. It was Sir Humphry Davy who, in the year 1810, first formed an electric arc and produced a real electric light. More than one electric lamp was patented during the first half of the nineteenth century; and in 1858, when Edison was only eleven years old, an electric lamp designed by Dubosc was used in the South Foreland Lighthouse in Kent.
You are then quite entitled to ask why it is that Edisonís name is always coupled with that of the electric light. In this chapter I will do my best to make the matter clear.
The electric light invented by Sir Humphry Davy was the arc lamp. Now the arc lamp consists of two carbon rods to which the terminals of a powerful battery are connected. The free points of the rods are separated by a short gap across which the current passes, forming a brilliantly luminous electric arc. Such a light is immensely powerful, and suitable only for illuminating, big spaces. It has various disadvantages, for at times it crackles and spits, while small portions of burned carbon drop from it. The arc light was too bright and too big for indoor use. What was wanted were little lights and a way of distributing the current to private houses just as gas is distributed. That was the problem to which Edison set himself.
Before I explain how he solved it, I want to go back a little and tell you something about Edison himself. Just as he is by far the greatest of living inventors, so the story of his beginnings is most interesting, for it shows how a poor boy, with no advantages of birth or education, can rise to an undreamed-of eminence. Edisonís father was Dutch, his mother Scotch, and he was born at Milan, Ohio, in 1847. His people were very poor; but his mother, who had been a teacher, gave him some schooling. He read everything he could lay hands upon, and at twelve became a newsboy on the Grand Trunk Line running into Detroit.
Edison made his living by selling papers, and spent his spare time in a little laboratory which he was allowed to fit up in one corner of a baggage car. Bottles and retorts he begged from the railway workshops. The editor of the Detroit Free Press gave him a quantity of old type, and with this he printed a paper of his own, and sold it on the trains. Often he got a piece of important news from a stationmaster, set it up at once, and sold it, so beating the newspapers which might be awaiting the passengers at the terminus. He called his paper the Weekly Herald, and one copy still survives, which Mrs. Edison has preserved. One day, while working in his train laboratory, a phosphorus bottle upset and caused a small fire. The conductor not only stopped his experiments, but lifted the boy by the ears, thus setting up the deafness from which the great inventor has suffered ever since.
Edisonís chief hobby was electricity, and his great ambition was to become a telegraph operator. Some time after the phosphorus disaster he saved the life of the small son of the stationmaster at Port Clements. The boy was almost under the wheels of a train when young Edison snatched him away. In return, the ladís father taught Edison telegraphy, and in due course he obtained the position he coveted at Fort Huron. Before very long he became extremely expert, and was able to take the messages more rapidly than any operator on the line. At last a man was put on as despatcher who was too rapid even for Edison. This led to Edisonís first real invention. He got two old Morse registers, and arranged them so that the dots and dashes were recorded by the first instrument and developed by the other at the desired rate of speed. So if news came in at the rate of forty words a minute, the pace could be reduced to twenty-five.
Edisonís next invention was an automatic repeater which could be attached to a line, and of its own accord would send a message onward. This device worked excellently; but, unluckily for Edison, the nephew of the manager was just completing a similar instrument, and the very unfair consequence was that Edison got the sack. He went to Boston, and there astonished his colleagues by the lightning speed at which he was able to receive. While in that city he took out his first patent for an electrical vote recorder, and went with his machine to Washington, where he showed it to the Chairman of a Congressional Committee who looked it over. "Young man," he said, "it works all right, and could not be improved upon. But it is the last thing we want here. Take it away."
"Then and there," says Edison, "I made up my mind that I would never again invent anything that was not wanted, and I believe that I have kept my vow."
In 1868 Edison gave up his position as telegraph operator, and determined to use his savings to become an inventor. He went to New York, and the very first day after his arrival walked down Wall Street, the financial center of the United States. He was attracted to the office of the Law Gold Indicator, where one of the first "tickers", or stock exchange indicators, was at work. It had gone wrong, and half a dozen workmen were vainly trying to find out where the trouble lay. Edison watched a while, then said that he thought he could put it right. Mr. Law rather scornfully told him to try. Edison merely moved a loose contact spring which had caught between two wheels, and the "ticker" at once began ticking again merrily. The workmen looked foolish, and Mr. Law asked Edison to step into his private office. He came out five minutes later with the position of manager at three hundred dollars a month.
At once he began to improve the indicator, and his reward was a cheque for forty thousand dollars. Now at last the young inventor had the capital he required, and set himself to real invention. His first great feat was the invention of duplex or quadruplex telegraphy. By the latter device two messages can be sent simultaneously along the same wire in opposite directions. He made a great deal of money, and started his famous workshops and laboratories at Menlo Park. And so at last he came to his great work on electric lighting.
It was in 1878 that he first saw an arc lamp, and at once the idea was born of lighting houses with electric light and so superseding coal gas. The forming of a multiple arc with which incandescent lamps should be used was, to a mind like Edisonís, comparatively simple, but to find a filament which would stand up without melting or short-circuiting was a very different matter. He tried platinum wire, but it melted. He tried an alloy of the rare metal iridium with platinum, but it would not stand. He tried silicon, boron, and a score of other substances. Carbon he did not try at first, because he knew that it oxidized so readily. But at last he was driven to
experiment with carbon, and after much difficulty and many failures succeeded, on October 21, 1878, in making a filament of cotton thread thoroughly carbonized. When this was tested it stood up to 275 ohms. Edison watched it, every minute expecting to see it burn out, every minute more and more pleased that it continued to burn. You will have some idea of Edisonís tremendous strength of mind and body when I tell you that he watched the lamp for forty-five hours without sleep and with very little food. Then at last the filament collapsed.
But now the inventor knew that he was on the right track. Carbon of some sort was what was needed for the perfect filament, and he set to work experimenting with every sort of carbon on which he could lay his hands. The best result was obtained from a filament of bamboo broken from an old fan. Edison set to work to study bamboos, and learned that there were twelve hundred varieties of the plant. He tried six thousand specimens, and spent a hundred thousand dollars on research. At last he found three sorts, all South American varieties, which were what he wanted, and was ready to give his new light to the world.
He determined to have a central station, and spent days studying maps of New York in order to discover the best situation for it. He finally bought two old buildings in Pearl Street, and there he installed the first electric-lighting plant, not only in America, but on this planet.
There were, however, still rocks ahead. Edison determined to have a high-speed engine, so went to a famous builder and said that he required a one-hundred-and-fifty-horsepower engine that would run at seven hundred revolutions per minute. The builder said it was impossible. "It is not," said Edison; "but if you cannot make it, I will find some one else who can." He did; but when the engine was installed, it nearly shook the building down. Edison had to get new engines which ran at three hundred and fifty revolutions and gave one hundred and seventy-five horsepower. These worked well; and on September 4, 1882, all was at last ready. He turned on the current, and so perfectly had everything been prearranged that the light service continued, with only one short stoppage, for eight years.
Edisonís success was so immense that all sorts of people tried to pirate his invention, and, like Morse and Bell, he had to fight desperately for his rights. Lawsuits went on for fourteen years; and when at last they were decided in his favor, his patent had but three years left to run. It may perhaps give you a further idea of the extraordinary thoroughness of Edison when I tell you that he has to his credit no fewer than one hundred and sixty-nine different patents on electric light alone, ninety-seven on dynamos, twenty on electric meters, twenty on storage batteries. In all he has taken out nearly two thousand different patents.
Edison never allows himself to be beaten. He has the rare faculty of being able to concentrate his vast mental energies upon a single problem, to the exclusion of all else. In an argument during a lawsuit concerning one of Edisonís patents counsel made a remark worth recording. Speaking to the judge, he said, "If your honor wished him to do so, Mr. Edison could go into a field of grass a mile square and select therefrom the most perfect blade." The learned gentleman was not far wrong, for the real Edison is a man of tireless industry, who gains his results by intense effort intelligently applied. With him it is an unalterable rule never to allow any new device to issue from his laboratory until it is absolutely perfect. "Genius is one per cent. inspiration and ninety-nine per cent, perspiration", is a favorite saying of this great American. You might almost call it his motto, for certainly he has never spared either brain or body in the pursuit of knowledge and new inventions.
Edison always draws a very broad line between "discovery" and "invention." In his idea, discovery is what he calls a "scratch", something that might be disclosed to any one, and for which very little credit is due. Invention, on the other hand, is the result of that peculiar mental faculty which not only perceives a new phenomenon but is able to apply it to a new use.
Yet one of Edisonís greatest achievements, the invention of the phonograph or talking machine, was in part, at least, inspiration. In his early work with automatic telegraph instruments working at high speeds, Edison made some experiments with embossed strips which were moved rapidly beneath a stylo or metal pen so as to vibrate it. In vibrating, this stylus produced a peculiar sound. Now an ordinary person might have heard this sound without attaching any particular importance to it.
Not so Edison. At this time the inventor was working on telephones as well as telegraphs, and consequently was studying acoustics, or the science of sound. All in a flash it came to him that, if the undulations on the strips could be given popular form and arrangement, a diaphragm could be vibrated so as to reproduce any desired sounds. In that moment the idea of a talking machine was born in Edisonís brain.
So much for the inspiration, but the problem before the inventor seemed a very stiff one. Whether what followed was also inspiration or whether it was the result of pure reasoning, I do not profess to know, but, at any rate, Edisonís next step was the idea that these undulations might be produced by the sounds themselves. It remained to find a substance capable of receiving the sound waves, and for this I believe that Mr. Edison used simply tin foil. He made a rough sketch of his model and handed it to one of his assistants, John Krusei, to construct.
The story is that Krusei stuck to it for thirty hours on end and finished it. Then, standing in his laboratory, with his assistants round him, Edison slowly turned the handle and spoke into the receiver the first verse of "Mary had a little lamb." The cylinder was turned back to the starting point, and there came, like an echo, the words which Edison had first spoken. Next day the inventor took the model down to the office of the Scientific American, and it is on record that no inventionónot even Bellís first telephoneóproduced such a sensation as this first crude talking machine. The patent for the phonograph was applied for on Christmas Eve, 1877, and the date is peculiarly appropriate, because I do not think that any other inventionónot even wirelessóhas done more to add to human happiness than the gramophone.
Although Edisonís very first phonograph was able to record and reproduce speech, its tone was harsh and the records were unsatisfactory. Edison, however, was too busy with other matters to perfect the invention, and this was done by Bell and his brother together with a partner named Tainter. It was they who first made the disc records resembling those used to-day. Since their time, very many improvements have been made, so that the phonograph of to-day will reproduce almost any sound with extraordinary clearness and perfection.
It may be interesting to tell just how the flat disc records used in the modern phonograph are made. A metal sheet is coated with a very thin film of wax, from which the sharp steel point moved by the recording diaphragm removes small portions, thus baring the metal beneath the wax. The sheet is then covered by an acid which eats into the bared portions, but does not touch the parts still covered by the wax. When the acid has done its work, the wax is removed, and there is left a negative record made of metal. It is from this negative that the vulcanite positives are prepared for the market. The modern record is so perfectly made that it can be used many hundreds of times without deteriorating, if proper care is taken.