From the 1924 book, A Popular History of American Invention. Original chapter title, “TALKING OVER A WIRE. THE STORY OF THE TELEPHONE.”
ON the afternoon of June 2, 1875, in the hot stuffy attic of Charles Williams’ electrical shop at 109 Court Street, Boston, a man and an apprentice lad were hard at work over a balky piece of electrical mechanism. For many weeks the two had been engaged on the invention of a telegraph by which they hoped to be able to send a number of messages over a single wire at the same time. But it was something more than this; it was to be a “harmonic” telegraph which would send, not click-like signals, but musical notes.
Despite every effort, the device stubbornly refused to operate as its inventor had long hoped and steadfastly believed it would. And yet on this memorable afternoon, without knowing it, they were about to make history. A new instrument was to take its place in human affairs. Inventive genius was to be rewarded in the birth of the telephone.
The man was Alexander Graham Bell, a young Scotsman who had come to Canada in 1870 to seek health and fortune in a new land. In 1872 he moved to Boston, and continued his experiments with sound-transmission. His assistant was Thomas A. Watson, an employee in the electrical shop of Charles Williams. As described by Watson, Bell was at this time “a tall, slender, quick-motioned man with pale face, black side-whiskers and drooping mustache, big nose, and high sloping forehead crowned with bushy, jet-black hair.”
For generations his ancestors had been interested in human speech. Bell himself was a master of the science of sound and an elocutionist of some note. While a mere lad he and his brother Melville had invented a talking device that gave a very good imitation of the word “mam-ma.” Melville made the lungs and vocal cords and Graham the mouth and tongue.
Adopting the profession of his family, Bell became a teacher of deaf-mutes. He taught a system of “visible speech” (teach in speech by lip-movement), invented by his father.
After completing his education he went to London where he made the acquaintance of Sir Charles Wheatstone, the inventor of the English telegraph. On this occasion he learned that the German physicist Helmholtz had vibrated tuning-forks by means of electromagnets. Fascinated, as he always was with anything relating to sound, this fact deeply impressed Bell.
If an electric current could be made to vibrate a tuning-fork, why should not a vibrating reed or fork be made to vary an electric current so as to reproduce sound? Reasoning in this way, Bell conceived the idea of a musical telegraph. Why should it not be possible to send as many messages over a single wire as there are notes on a piano? This was the idea with which Bell started, and from it developed the telephone.
Shortly after coming to America, Bell was engaged by the Board of Education of Boston to introduce his system of visible speech in a school for deaf-mutes that had just been established in that city. His work met with great success, and he was soon appointed to a professorship in Boston University. Later he established a school of his own and, absorbed in his professional work, he had little time to think of a musical telegraph. Still the idea persisted.
HOW BELL’S TWO PUPILS HELPED HIM
About this time there came into Bell’s life, two young people destined to have a profound effect upon his future career. He received as a private pupil a little deaf-mute, Georgie Sanders, who lived with his grandmother in Salem. As part payment for his services Bell went to live in the Sanders’ home, where he was allowed to have a workshop in the basement. He also made a warm friend of the boy’s father, Thomas Sanders, without whose sympathy and financial assistance the invention of the telephone would have been impossible.
There also came to him at this time another private pupil, Mabel Hubbard, a girl of fifteen who had lost her hearing in infancy. Not only did she take the keenest interest in his electrical experiments, but four years later she became his wife, and her father, Gardiner G. Hubbard, a prominent lawyer of Boston, did more than any other one man to make a commercial success of the telephone.
Gradually the idea of a musical telegraph thrust every other thought from Bell’s mind. He abandoned his school. Only two pupils remained, Georgie Sanders and Mabel Hubbard. Their fathers financed his work, for they had faith in Bell and believed that his idea would bring fame to him and wealth to them all. A new era would be inaugurated in the art of communication.
|Alexander Graham Bell just a few years later with his wife Mabel and daughters.|
In his laboratory at Salem, Bell worked incessantly. Sleep was a secondary consideration. Sanders says: “Bell would often awaken me in the middle of the night, his black eyes blazing with excitement. Leaving me to go down to the cellar, he would rush wildly to the barn and begin to send me signals along his experimental wires. If I noticed any improvement in his apparatus he would be delighted. He would leap and whirl around in one of his ‘war dances,’ and then go contentedly to bed. But if the experiment was a failure he would go back to his work-bench to try some different plan.”
Slowly there dawned upon Bell’s mind a still larger idea. “If I can make a deaf-mute talk,” he said, “I can make iron talk” At first only a dream, this idea of sending the spoken word itself over an electrified wire grew into a deep conviction. His interest in a musical telegraph began to vanish. With an enthusiasm scarcely ever equaled, Bell set himself to the invention of an actual talking telegraph. But Sanders and Hubbard had no faith in his new project, and refused further assistance unless he should devote at least a part of his time to the musical telegraph. Therefore he divided his time between the two inventions, working faithfully for a portion of each day upon his original idea. But his heart was in the telephone.
BELL’S EXPERIMENTS WITH A DEAD MAN’S EAR
At the same time Bell had been trying to improve his system of visible speech. In these experiments he used a speaking-trumpet as transmitter, and a harp as receiver. In this way he discovered that he could make sound waves plainly visible by speaking against a drum or membrane to which he had attached a short pointer, or stylus.
Doctor Clarence J. Blake of Boston suggested the use of a human ear, and provided for Bell’s use one that he had taken from a corpse. Bell then constructed an apparatus, of which the dead ear formed a part, and which made it possible for the spoken voice to trace a record of its vibrations in beautiful curves on smoked glass.
In the gray light of his basement laboratory Bell must have presented a diabolical appearance as he shouted into this dead man’s ear. The inhabitants of Salem might well have thought that the witches of old had come back to disturb once more their peaceful town. Here was a delicate ear-drum which, in response to the sound waves of the human voice, set into vibration the heavy bones behind it. “Why,” he asked himself, “should not a vibrating iron disk set an iron rod or an electrified wire into vibration ?” How this was to be accomplished, he did not know, but he felt he was moving in the right direction.
Just at this point, while on a visit to Washington, Bell met the venerable Joseph Henry, who for a generation had been the pioneer of electrical science in America. From Henry, Bell received the utmost encouragement. Replying to Bell’s statement that he did not possess sufficient electrical knowledge to perfect the telephone, Henry said: “Get it.” This was just the spur that Bell needed. He returned to his workshop with a mighty determination to succeed.
|Joseph Henry scientist and director of the Smithsonian Institution gave young Bell advice and encouragement.|
Like Morse, of telegraph fame, Bell’s early days were beset with poverty. His professional income had practically vanished. His two remaining pupils barely supplied him with the necessities of life. Sanders and Hubbard provided funds for his experimental work only. Writing to his mother at this time, he says:
“I am now beginning to realize the cares and anxieties of being an inventor. I have had to put off all pupils and classes, for flesh and blood could not stand much longer such a strain as I have had upon me.”
This was in 1874. Bell was now established in the attic of Williams’ electrical shop in Boston. Sanders and Hubbard were paying his assistant, Thomas A. Watson, nine dollars a week, and the inventors were dividing their time between the musical telegraph and the telephone.
|BELL’S “HARMONIC TELEGRAPH.” It was with this instrument that Alexander Graham Bell began the series of experiments which finally culminated in the invention of the telephone. Instead of sending signals over a wire, which would be received as intelligible clicks, Bell conceived the idea of sending musical notes which could be identified by their pitch. Clock-spring reeds were vibrated electromagnetically, very much like the clappers of house-bells. One day a clock-spring became attached to its magnet, with the result that a feeble sound was heard at the receiving end, the current flowing continuously through the line. By accident, the fundamental principle of the telephone was thus discovered.|
THE TELEPHONE IS INVENTED
We now come to the memorable afternoon with which we began this chapter. Alexander Graham Bell’s telegraph comprised, among other things, clock-spring reeds which were vibrated by electromagnets, very much like the clappers of electric house-bells. Watson was sending, and Bell receiving.
As Watson pressed down the key at his end, to make the clock-spring at the sending end of the wire vibrate, the contact points fused together. As a result, the clock-spring was simply held down by its electromagnet, just as an ordinary horseshoe magnet attracts and holds a needle. Watson tried to pluck the spring free. This made it vibrate over the electromagnet. Bell, with blazing eyes and alive with excitement, came rushing into the room. A feeble sound had at last passed over the wire, and his keen ear had caught it. “What did you do then ?” he demanded of Watson. “Don’t change anything. Let me see.”
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|BELL’S EXPERIMENTAL TELEPHONE (1875). After having discovered the principle of the telephone accidentally with the aid of his “harmonic” telegraph, Bell instructed his assistant, Watson, to build this instrument. The armature of the electromagnet had the form of a hinged iron lever, carrying a stud at one end, which pressed against the centre of a stretched membrane of goldbeater’s skin. Speech sounds were actually transmitted with this instrument in 1875, but it served chiefly the purpose of revealing the feasibility of the plan.|
The first faint cry of the baby telephone had passed into history. In that moment a new epoch in the art of communication was ushered in. The fundamental principle of the modern telephone was operating in that simple apparatus. By accident the current was flowing continuously through the electromagnets and the line. The plucking of the spring had varied the intensity of this current and thrown into vibration the corresponding clock-spring at the receiving end of the line.
The discovery, one of the greatest in all history, had been made. The rest was a mere matter of detail and mechanical perfection. It seems easy now. But the inventors worked for forty long weeks before they made their telephone talk.
The very afternoon of the discovery, Bell gave Watson directions for making the first telephone. Watson says: “I was to mount a small drumhead of gold-beater’s skin over one of the receivers, join the centre of the drumhead to the free end of the receiver-spring, and arrange a mouthpiece over the drumhead to talk into. I made every part of that first telephone myself, but I didn’t realize while I was working on it, what a tremendously important piece of work I was doing.”
|Alexander Graham Bell and his assistant Thomas A. Watson.|
Forty weeks of patient experimentation and then, on March 10, 1876, Watson heard distinctly through the telephone-receiver this message: “Mr. Watson, please come here, I want you.” It was a message that proved to be as immortal as Morse’s. “What hath God wrought?”
Progress now became rapid and certain. Watson says: “The telephone was soon talking so well that one didn’t have to ask the other man to say it over again more than three or four times before one could understand quite well, if the sentences were simple.”
The fates were kind to Bell. The stage had already been set for the coming of his invention. The Centennial Exposition was just opening in Philadelphia, and this afforded precisely the opportunity that he needed. Bell had not expected to attend the exposition himself. Overcome at the grief of his fiancée, when at the railroad station she learned that he would not accompany her, Bell rushed madly after the moving train and climbed aboard.
Hubbard had secured for Bell a small table in an out-of-the way corner of the Education Building for the exhibition of his apparatus. No one visited him. No one was interested in his invention. It was only a “toy.” What if speech could be sent over a wire? Of what value could that be? No one had the vision to see the tremendous possibilities hidden within this crude piece of mechanism.
|THE FIRST TELEPHONE THAT TALKED. This is the transmitter used by Bell when on March 10, 1876, be telephoned to his assistant: “Watson, please come here, I want you.”|
But Bell patiently awaited the judges’ tour of inspection. At last they came. It was just at dusk. Tired and hungry after a long day of continuous inspection, they were in no mood to waste time over a useless plaything. One or two approached the table, picked up the instrument, fingered it listlessly. As the judges were about to pass on, there was enacted a scene worthy of the brush and genius of a master artist.
Dom Pedro, the young emperor of Brazil, followed by a company of gaily attired attendants appeared, and, rushing up to Bell, greeted him with great fervor. Dom Pedro had visited Bell’s school for deaf-mutes years before and had been pleased by his system of visible speech. He was intensely interested in the new invention. Walking to the other end of the line, Dom Pedro placed the receiver to his ear. Bell spoke and the emperor dropped the instrument, exclaiming: “My God, it talks.”
There in the twilight stood the judges, awed and silent witnesses of this picturesque but momentous event. One by one they came forward, utterly forgetful of weariness and hunger, each in his turn eager to test this latest marvel of science and invention. There were Joseph Henry and Sir William Thomson, the latter declaring it to be “the most wonderful thing he had seen in America.” From that moment Bell’s telephone became the most popular exhibit of the exposition, and overnight its inventor leaped to world fame.
Bell’s original telephone was exceedingly simple. About one pole of a permanent bar magnet was wound a coil of fine copper wire. One end of the wire was grounded, while the other went to the line. In front of the pole was mounted a soft iron disk to which was attached the mouthpiece. The receiver was of identical construction.
The sound waves of the voice, striking upon the sending disk, made it vibrate. This vibration caused the current in the line to vary. The disk of the receiving instrument was vibrating in sympathy with these electrical variations in the line. Hence the receiving disk vibrated exactly as the sending disk vibrated when words were spoken against it. The receiving disk therefore talked.
In other words, Bell first changed sound into electrical current, and then changed the current back again into sound. The same instrument served both for transmitter and receiver. But simple as these instruments were, they worked on the same principle as those of to-day.
|BELL’S ORIGINAL INSTRUMENTS NOW PRESERVED IN THE NATIONAL MUSEUM, WASHINGTON. The transmitter and receiver were of substantially similar construction. About one pole of a permanent bar magnet was wound a coil of fine copper wire. In front of the pole was mounted a soft-iron disk, to which the mouthpiece was attached. The sound waves of the voice, striking the sending disk, made it vibrate. This vibration caused the line current to vary. The disk of the receiving instrument vibrated in sympathy with these electrical variations in the line.|
INTRODUCING THE TELEPHONE TO THE PUBLIC
Although the telephone had taken rank as among the most wonderful bits of mechanism ever produced, the interest in it was still only that of curiosity. No one could see any possible use for it. Its inventor had won fame, not fortune. The public, remaining skeptical, had to be educated. To this task of winning popular favor, Gardiner G. Hubbard immediately devoted himself. With an enthusiasm and a breadth of vision rarely equaled elsewhere in the history of invention, he became the apostle of the telephone.
Hubbard’s first step was to arrange a series of ten lectures to be given by Bell and Watson. The first demonstration was given before the Essex Institute of Salem. Having no lines of their own, they obtained permission to use a telegraph line for the occasion. Bell gave the lecture while Watson, located in the Boston laboratory, provided the entertainment.
|INTRODUCING THE TELEPHONE TO THE PUBLIC. The public had to be taught the principle and function of the telephone. Hence, Gardner Hubbard, Bell’s father-in-law, arranged a series of lectures to be given by Bell and Watson. The first demonstration was given before the Essex Institute of Salem, in 1877. Watson, in Boston, played musical instruments and sang. The audience was delighted. By courtesy of Mann & Company. From the Scientific American of March 31, 1877.|
At the request of Bell, Watson played various musical instruments, and although not a singer, he was required to render such favorite songs as “Auld Lang Syne” and “Do Not Trust Him, Gentle Lady.” The audience was delighted. Newspaper editors featured the performance. Invitations to repeat the lecture came like a flood. And yet the interest was chiefly that of curiosity. Still these lectures did bear fruit. They acquainted the public with the uses and purposes of the telephone, and on the small admission returns, Bell was able to marry and to sail for Europe on his wedding trip.
On the occasion of one of these lectures, Watson invented the first telephone-booth. In order to make his audiences hear, he was compelled to shout into the mouthpiece of the transmitter. This annoyed his landlady, and strained relations had already arisen between them. Knowing that on the Boston-New York trial he would be required to use an extraordinary amount of lung power, Watson removed the blankets from his bed and arranged them in a sort of loose tunnel. In this soundproof booth he was able to shout as loudly as he pleased without fear of being heard.
THE BELL COMPANY AND THE WESTERN UNION
While Bell was in Europe Hubbard organized the “Bell Telephone Association,” with Bell, Hubbard, Sanders, and Watson as partners. The first out-of-doors telephone-line to be established was between the Williams’ electrical shop in Boston and Mr. Williams’ home in Somerville. Then the unexpected happened. A man from Charlestown, named Emery, came into Hubbard’s office one afternoon in May, 1877, and laid down twenty dollars for the lease of two telephones. It was the first money ever received for a commercial telephone. In the promise it gave of future rewards it seemed like a million dollars.
In that same month, too, the first crude exchange was established in Boston. Six telephones were loaned to Mr. Holmes, the proprietor of a burglar-alarm system, who installed them in six banks and connected them to a central station.
|THE FIRST TELEPHONE SWITCHBOARD. E. T. Holmes, of Boston, proprietor of a burglar-alarm system, had six telephones installed in six banks, and connected with a central station. This was in 1877. Hence the first “central” was a switchboard by day and a burglar alarm by night.|
Very soon exchanges were established in New York, New Haven, Bridgeport and Philadelphia. By August, 778 telephones were in use. The demand for them was so great that they could not be supplied. They were also expensive to manufacture, and, despite the appearance of prosperity, the company was on the verge of financial ruin. The only member of the company who had money was Sanders, and his fortune was not large.
Not realizing the value of his invention, Bell had already offered it to the powerful Western Union Telegraph Company for $100,000. But the “scientific toy” was rejected. The Western Union never dreamed that its monopoly of wire communication could be shaken until several of its New York patrons removed the printing telegraph-machines from their offices and replaced them with telephones.
Alarmed at this invasion of their private domain, the Western Union sat up and took notice. They at once organized the “American Speaking-Telephone Company,” with a capital of $300,000, and enlisted the services of Gray, Edison, and Dolbear as electrical experts and inventors.
|Telegraph operators. Western Union, well in command of the telegraphing service industry, did not see, at first, the future in the Bell’s telephone. When they did, they tried to catch up.|
BELL’S RIVAL CLAIMANTS
On March 7, 1876, Bell had been granted a patent on his invention. This has been described as “the most valuable single patent ever issued.” It is a remarkable fact that on the same day that Bell filed his application for a patent, Elisha Gray filed a claim for a similar one. Gray had risen from a blacksmith’s apprentice to a professorship in Oberlin College. He had invented a musical telegraph that really worked, and later he claimed to be the rightful inventor of the telephone.
The Western Union, seizing upon these claims, began suit against the Bell Company to establish the rights of Gray. Although beset with poverty, the little group of telephone pioneers fought the attack with the help of the ablest lawyers of Boston. It was conclusively demonstrated that Bell was the rightful inventor of the telephone. The Western Union officers made peace and surrendered to Bell a monopoly of the telephone field, retaining for themselves similar privileges in the domain of telegraphy.
The result was magical. The Bell stock shot up to $1,000 a share. At this point the original promoters sold out their interests, each receiving a comfortable fortune, and turned the development of the business over to other men.
But rival claimants did not cease their fight. Back in 1861 Philip Reis, the son of a poor baker in Frankfurt, Germany, had invented an electrical contrivance that would carry a tune but could never be made to talk. It worked upon the principle of a make-and-break telegraph and not on the variation in the intensity of the electric current.
Professor Amos E. Dolbear improved this device and claimed to be the original inventor of the telephone. But after a long legal battle, the courts decided against him. When produced in court, his telephone refused to work, and, in extenuation, one of Dolbear’s attorneys vouchsafed: “It can talk, but it won’t.” In all, Bell and his company were compelled to fight more than 600 lawsuits to maintain their rights. No other patent has ever been more bitterly contested, and no claim to a great invention more clearly proven.
|Drawing from Bell’s patent application.|
Back in the midnight of financial chaos and legal battle, Edison invented for the Western Union a transmitter that made their instruments vastly superior to those of the Bell Company. The principle consisted in varying the electric current by varying the pressure between two contact points. In 1876 a poor German boy, Emil Berliner, who had come to this country a few years before, became fascinated with the telephone and started out to invent one on entirely new lines. The result was a transmitter identical in principle with that of Edison, invented but two weeks earlier. Since, however, Edison was in the service of the Western Union, Berliner’s claims were entirely ignored.
But fourteen years later the Supreme Court of the United States declared Berliner to have been the original inventor of the transmitter. Edison, without any knowledge of Berliner’s device, greatly improved it by substituting soft carbon in place of steel for the contact points. Professor David E. Hughes of Kentucky invented a carbon microphone which Francis Blake of Boston changed into a practical transmitter.
|EARLY BLAKE TRANSMITTER. Professor David E. Hughes invented a carbon microphone which Francis Blake, of Boston, changed into a practical transmitter.|
The Blake transmitter was as good as Edison’s, and the Bell Company bought it, thus placing them on an equal footing with the Western Union. The idea of using carbon in the form of small granules was that of the Reverend Henry Hunnings, an English clergyman. An expert of the Bell Company named White, developed the transmitter into its present form.
After Western Union had failed in their attack on the Bell patents, public confidence was captured and business grew so rapidly that a general manager became necessary. For this post, Hubbard selected a young man named Theodore N. Vail, the general superintendent of the Railway Mail Service, whose granduncle, Stephen Vail, had built the engines for the first steamship to cross the Atlantic.
In executive ability and sheer genius for organization, Theodore Vail has never had a superior He came to a bankrupt company whose affairs were in utter chaos. But his enthusiasm was unbounded; his faith in the possibilities of the telephone never faltered. In his prophetic vision he saw the future as few men have ever done. In 1879 he said: “I saw that if the telephone could talk one mile to-day, it would be talking a hundred miles to-morrow.”
Under his direction funds were raised, legal battles fought, agents licensed, exchanges established, and many hundreds of miles of wire strung. It was his dream to make the telephone business a national institution. His employees were infected by his enthusiasm. “It was work without ceasing, days, nights, Sundays, and holidays.” Without Theodore N. Vail the Bell Company might have died in infancy.
|Theodore Vail made the Bell Company successful.|
TELEPHONE APPARATUS AND THE SWITCHBOARD
When the telephone came into public use, one of Watson’s first tasks was to devise some sort of signaling mechanism. “It began to dawn on us,” he said, “that people engaged in getting their living in the ordinary walks of life couldn’t be expected to keep the telephone at their ear all the time waiting for a call, especially as it weighed about ten pounds then and was as big as a small packing-case.”
The original method of calling a subscriber was by thumping on the transmitter diaphragm with the butt end of a pencil. Then Watson devised a special kind of “thumper” which was operated by turning a button on the outside of the telephone-box. He followed this shortly after with the familiar hand-operated magneto-electric call-bell, still widely used on country lines.
|THE FIRST MAGNETO CALL. The original method of calling a subscriber was by thumping on the transmitter diaphragm with the butt end of a lead-pencil. Then Watson devised a special kind of “thumper,” which was operated by turning a button on the outside of the telephone-box. He followed this with the magneto-electric call-bell, still widely used on country lines, and of which this is the first model.|
In the early days of telephoning this notice was usually posted at stations: “Don’t talk with your ear, nor listen with your mouth.” This was the period, too, when all the farmers waiting at a country grocery would rush out and hold their horses when they saw any one preparing to telephone. But the improved transmitter banished the single instrument for both talking and receiving and greatly increased the efficiency of transmission.
The early “centrals” were exceedingly crude. The first telephone switchboards were built on the plan of telegraph-switchboards. They were good enough for a few lines, but not for thousands. Boys, not girls, were employed as operators, and the service was wretched. The boys ran about like mad and pandemonium reigned. It required half a dozen boys and as many minutes to answer a single call. Impudence was a telephone characteristic; there was a never-ceasing babble of noise, and tedious delays were the rule.
Then came a respite. The boys were banished and girls took their places. More important still, Charles E. Scribner, the “wizard of the switchboard,” took his place among the ranks of the telephone inventors. Scribner connected himself with the Western Electric Company of Chicago, the largest manufacturers of telephone equipment in the world.
To the genius of Scribner more than to any other one man, we owe the modern switchboard. In his perfection of it he has taken out more than 1,000 patents. It is one of the most intricate pieces of mechanism known to science. In its completed form one of these distributors of human speech may have as many as 2,000,000 parts.
|C. E. SCRIBNER, Who has patented more than 900 telephone inventions.|
A MODERN EXCHANGE OR “CENTRAL”
Let us enter a modern “exchange” and see how a Scribner switchboard operates. In any large exchange there are two sets of operators, the “A” and the “B.” In a New York City exchange each “A” operator tends about 40 or 50 lines direct from the subscribers, and connects them through trunk lines with the other exchanges of the city.
If 5,000 lines enter this exchange, there must be about 100 “A” operators. The “B” operators handle the calls coming to this exchange from the other exchanges of the city. If there are 50 other exchanges, there will be 50 “B” operators besides 1 or 2 to handle calls from the “A” operators of this same exchange.
On the horizontal shelf in front of the “A” operator is a double row of cords, a pair for each subscriber she attends. In front of these is a double row of small electric lamps. One of these lamps is connected with the circuit of the calling subscriber, and the other with that of the subscriber called. In front of the lamps is a row of listening keys; and in front of the keys a row of buttons for registering on the subscriber’s meter every call he makes.
At the bottom of the upright panel are the rows of subscribers’ “jacks” (contact sockets, connecting with the lines), and under each jack is a tiny electric lamp. Above them is a large number of trunk-line jacks, one set leading to each of the other exchanges of the city. To the immediate left of the operator’s position is a group of circuit calling-keys, by which she puts herself temporarily in connection with the “B” operators at the other exchanges of the city.
|EARLY “CENTRAL” SWITCHBOARDS.|
At each of the “B” panels are jacks for all the subscribers’ lines that enter that exchange. In one New York City exchange there are as many as 10,199. If there are 50 “B” operators, each subscriber’s line is “fanned out” into as many branches, one for each operator.
Then, to one “B” panel come all of the trunk lines from some other one exchange of the city, these lines ending in a row of cords on the horizontal shelf. To the next panel come all the trunk lines from some other exchange, and so on. In front of the row of cords at each position is a row of small electric lamps.
You lift your receiver from the hook, and immediately a signal lamp lights. The operator answers when she sees the light. Suppose your exchange is Cortlandt, and you are calling Spring 1709. Immediately the “A” operator who answers your call presses the Spring Exchange button at her left, and gives the “B” operator there the number wanted, whereupon the “B” operator makes the connection desired.
After either of the subscribers hangs up his receiver, the signal lamp in front of the “A” operator corresponding to his cord will light. When both of the lamps light she knows that the conversation is ended, and removes both cords from their jacks. This lights the signal lamp before the “B” operator in the Spring Exchange, and she removes the trunk line cord from its jack. The lines are now free for another call.
If a subscriber is not answered by central at once, the moving up and down of the receiver-hook flashes the signal lamp, calling the operator’s attention. This may be done by either party.
|BOYS, NOT GIRLS, MANNED THE EARLY CENTRALS. It required about half a dozen boys and as many minutes to answer a signal call. J. J. Carty, now vice-president of the American Telephone & Telegraph Company, was once a switchboard-boy. This is a contemporaneous picture of the Cortlandt Exchange, New York, in 1879.|
|RICHMOND (VA.) SWITCHBOARD OF 1882. Boys were soon banished from the central switchboards and girls took their places. The switchboards were improved, so that connections could be more easily made.|
|INTERIOR OF THE “CHELSEA” EXCHANGE, NEW YORK. A modern multiple switchboard of this type may be 250 feet long. It is divided into “A” sections and “B” sections which are on separate sides of the room. The “A” sections handle only connections to be made with the exchange’s own subscribers. Calls for subscribers connected with other exchanges are switched to the “B” sections. These manually operated switchboards will soon be obsolete, their place being taken by automatic machines.|
THE AUTOMATIC GIRLLESS “CENTRAL”
A little more than thirty years ago there lived in Kansas City, Mo, an undertaker named Almon B. Strowger. Strowger got the idea that the switchboard operator of his local exchange was in conspiracy with one of his competitors to ruin his business by falsely reporting his line “busy.” The only remedy for such a difficulty; he concluded, was a “girlless” exchange.
Therefore he began spending his odd moments in devising such a switchboard. A few days later Joseph Harris, a travelling man from Chicago, came into Strowger’s office. Strowger told Harris of his idea and showed him a “foolish contraption” made from a collar-box, some pins, and a lead pencil. Harris was immediately interested. Later he said, “Others laughed at the ‘crazy’ undertaker, but his fool contraption didn’t seem funny to me.”
Strowger moved to Chicago, where, in 1891, together with Harris and a number of others, he formed a company called the “Strowger Automatic Telephone Exchange.” Fortunately they interested in their enterprise, Mr. A. E. Keith, a young electrical engineer from the Brush Electrical Company of Baltimore. To the genius of Mr. Keith is due the modern automatic “central,” or machine-switching exchange.
To tell the story of the early struggles of this company would require a volume. We may simply say that intelligent effort and indomitable perseverance have won the day. The factory of the company in Chicago employs 3,000 workers, and covers ten acres of floor space. Their system covers the earth. Dozens of cities in this and other countries have used machine-switching exchanges for more than twenty years.
|MODERN MANUALLY OPERATED TELEPHONE SWITCHBOARD. This is a detail of a “B” board. The operator is engaged in connecting a subscriber from another exchange with the subscriber called.|
Already New York City has begun to convert her system to the automatic basis, and in a few years’ time the “hello” girl will be only a memory.
How does the automatic exchange work? The engineer in charge of the installation work in one of our largest cities told the author he had studied the system night and day for three weeks, before he felt that he understood it. Indeed, to see the bewildering maze of lines, switches, and relays, and then watch their automatic operation, one is staggered by the revelation of such human ingenuity and mechanical perfection.
The subscriber’s instrument differs from the usual one only in having at its base a calling device known as a “dial.” The small finger-holes of the dial contain the digits from 1 to 9 and 0; sometimes, they also contain letters. Lifting the receiver from the hook causes the “line switch” to connect the calling line to a device known as a “selector” and to send back the “dial tone” which corresponds to “number, please ?”
Now, instead of giving the number in the usual way, the subscriber “dials” it. He puts his finger in the hole of the dial corresponding to the first digit of the desired number, brings it around to the stop, releases it, and repeats the operation with each of the other digits.
Dialing the first digit causes the “first selector” to pick out an idle “second selector” in the proper thousand group. The second digit causes this switch to select the particular hundred group wanted. The third and fourth digits control the “connector switch” which joins the calling line to that of the called subscriber.
At the same time it sends the ringing current over the called line. If the line is busy, automatically the “busy tone” comes back to the person calling. Placing the receiver on the hook, when the conversation is complete, instantly breaks the connection and clears the apparatus for another call.
|BEHIND THE SCENES IN A GIRLLESS CENTRAL. Girls are giving place to machines in telephone exchanges. The subscriber operates a dial on his telephone and the automatic machines make the connection. This is one of the automatic centrals developed by the American Telephone and Telegraph Company along lines originally laid down by Strowger.|
So completely has the mechanism been developed that both hand and automatic systems may be used in the same city at the same time. Every detail has been perfected: coin-boxes, toll-calls, long-distance, and “information.” But in handling long-distance and toll-calls, and for certain other services, the assistance of operators is still required to a limited extent.
The cost of installation is greater for the automatic than for the “girl” exchange, but, once installed, its operation is more economical. The automatic system insures greater speed, absolute secrecy, and it is always “on the job.” It never sleeps, never has special hours, never grows weary. It represents one of the greatest triumphs of telephone engineering, and its universal adoption is bound to come in the near future.
GENERAL JOHN J. CARTY’S INVENTIONS
In 1880 a nineteen-year-old lad entered the employ of Thomas Hall at 19 Bromfield Street, Cambridge, Mass. Thomas Hall kept an electrical shop and the lad was John J. Carty, now vice-president of the American Telephone and Telegraph Company. He has been identified with the principal achievements in developing the art of telephone communication in this country. He has largely created the profession of telephone engineering. Only the other day, as we shall presently see, he startled the world with the greatest triumph in the art of communication I that has ever been known.
Of that early experience in Hall’s electrical shop, Carty says: “I swept out the place, cleaned about there, did errands, mixed battery solutions, and got a great deal of experience in one way or another.” As the result of a prank that he and the other boys of the shop played on the boss, Carty was “fired.” His next job was as “hello boy” in a telephone exchange in Boston.
“The little switchboards of that day,” he says, “were a good deal like the automobiles of some years ago—one was likely to spend more time under the switchboard than sitting at it. In that way I learned a great deal about the arrangement and construction of switchboards.” Eventually Carty got in touch with Scribner and as a result of this and his own later experience became expert in the construction and installation of switchboards. Later he was placed in charge of the switchboard department of the Western Electric Company.
His first great triumph was to overcome the babble of weird underground noises that day and night played over the telephone circuits. He did this by substituting a return wire in place of the earth, which had been used to complete the circuit in all of the early lines. The result was magical. The tantalizing interruptions disappeared, and quiet has since reigned.
Vail then brought Carty to New York and assigned him the task of putting the maze of overhead wires in underground cables. This he did in record time and at half the former cost, devising in the process cheaper and better cables. For the individual batteries along the line, he substituted the central battery system. The “bridging bell” by which several subscribers may be put on a single line without their signaling apparatus interfering with the talking of the others was Carty’s work. These are but a few of his many services.
|A TELEPHONE CABLE BOUQUET. This picture shows a section of a 1,200-pair cable. Such a cable contains 2,400 wires, encased in a leaden sheath less than three inches in diameter.|
TELEPHONING ACROSS THE CONTINENT
The telephone system grew with marvelous rapidity. In 1892 New York was talking with Chicago. The service was soon extended to Milwaukee, Omaha, and then it took a still longer stride to Denver. But, like the famous beanstalk of fairy lore, the genie of the telephone system did not stop. Presently the dream of transcontinental communication became a fact. Over the hills and valleys, across the plains, up the mountainsides, through the sagebrush, and down to the Golden Gate in less than a second is now a commonplace of the telephone romance.
Of tremendous importance to telephony was the invention of the “loading coil” by Professor Michael Pupin, of Columbia University. In 1874 Michael Pupin, a poor Serbian lad of fifteen, landed at Castle Garden, New York City, with only five cents in his pocket, and utterly unable to speak the English language. His first encounter with American life was in the shape of a fistic combat with Battery bootblacks, in which he demonstrated his superiority as an amateur pugilist.
After a short period on a farm, where he learned to speak English, he returned to New York. Suffering the bitter experiences of poverty and wholly without influence, Pupin slowly worked his way through Cooper Union and Columbia University. He partially met his university expenses by giving lessons in wrestling and boxing. After further study abroad he came back to a professorship at Columbia, and has been a member of the faculty since 1888.
His first discovery was the “tuning principle” in wireless, an invention which he sold to the Marconi Company for a large sum. His next and most important invention was the “loading coil” which first made it possible to telephone cheaply over long distances.
It is not easy to explain just what is a “loading coil,” nor what it does. Tie a heavy rope to a post; shake it with your hand ever so little, and a wave runs along the rope back and forth. Repeat the experiment with a thread. The thread must be shaken harder to obtain a similar wave. Suppose you hang weights from the thread and then shake it. Now it becomes easier to get a response, a wave.
Pupin’s coils are somewhat like these weights. They load the line and make it easier to send electric waves. The idea of so “loading” a telephone line was not original with Pupin. No one knew just where the coils should be placed. There were thousands of possible intervals, and it would have taken years to determine the correct intervals by actual experiment.
Pupin worked out a mathematical formula, after many weary months, which told him exactly where the coils should be placed. The telephone company is said to have paid Pupin $500,000 for his American patent rights. He probably made as much more out of his European patents. In New York City alone, the Pupin coils save the telephone company $3,543,000 a year, because they made possible the substitution of small wires for large ones in telephone cables.
|BROADWAY AND JOHN STREET, NEW YORK, IN 1890. As the use of the telephone grew, the streets of cities were threaded with a maze of telephone wires. This is a view of Broadway and John Street in 1890. The danger of these overhead wires was such, and the interruption to telephone traffic in storms so intolerable, that the telephone company laid its wires in conduits underground.|
Another invention which has been of tremendous importance in the development of long-distance transmission as well as in many recent developments of the telephone, is the Lee De Forest vacuum-tube amplifier. This marvelous little device, described in the chapter on radio communication, has been brought to a high state of efficiency. It was invented by Lee De Forest in 1906, and patented a year later.
It controls and magnifies the electric current sent out through the line, and following its introduction, the human voice travelled from New York to San Francisco with remarkable clarity and speed. The transcontinental line, opened on January 25, 1915, is 3,390 miles long.
At frequent intervals are vacuum-tube amplifiers, or repeaters. There are two circuits, each consisting of 6,780 miles of “hard drawn” copper wire, weighing 2,960 tons. In the loading coils of each circuit are 13,600 miles of fine insulated wire only four thousandths of an inch in diameter. The line is strung on 130,000 poles and crosses 13 States.
On the historic afternoon of January, 1915, Doctor Bell in New York speaking into an exact reproduction of his original instrument, was clearly heard by Watson in San Francisco.
Doctor Bell said again, as on that other historic day, thirty-nine years before: “Mr. Watson, please come here, I want you.” And Watson replied: “It would take me a week now.” What a magnificent chapter brimming over with glorious achievement and marvelous progress this incident closed!
|ALEXANDER GRAHAM BELL OPENING THE NEW YORK-CHICAGO LINE, OCTOBER 18, 1892.|
BY WIRE AND WIRELESS
Immediately following the triumph of transcontinental telephony, General Carty and his staff of engineers began the development of wireless communication in conjunction with wire-telephoning. How this was accomplished is told in detail in another chapter in this book dealing with radio. Success, however, was rapid and certain.
On September 29, 1915, Theodore N. Vail, sitting at his desk in New York, sent his voice by wire to Arlington, where it was amplified and transmitted to the great wireless naval station. From there, radiating with the speed of light in all directions, the boundless ether carried the electromagnetic waves to Carty at Mare Island, California, where he heard and conversed with Vail as easily as though they had been in adjoining rooms. The following day messages were picked up in Honolulu, 5,000 miles distant.
In May of 1916, Secretary Daniels, sitting at his desk in Washington, with magic ease and speed, conversed at will with every naval station from ocean to ocean, and from the Gulf to the Lakes. Not only this, but the secretary, by wire and wireless, also talked with Captain Chandler of the New Hampshire off the Atlantic coast, and kept in communication with him for twenty-four hours.
In the spring of 1921, under the direction of Carty, telephone communication was opened by cable from Havana, Cuba, to Key West, a distance of 115 miles, thence by wire to Washington, New York, San Francisco, and Los Angeles, and then by wireless 29 miles to Catalina; a total distance of 5,500 miles. This is the longest submarine telephone cable in the world.
|Theodore Vail Makes the first transcontinental telephone call. Later, calls were relayed by wireless to greater distances.|
Late in 1918, Theodore N. Vail announced the invention of the “Multiplex Telephone,” by which five conversations might be carried on over the same circuit at the same time, four in addition to the one provided by the ordinary methods.
Five messages travel over a common pathway and yet are completely separated at the other end. All this has been accomplished by means of magical vacuum tubes, each so adjusted that it receives only the words (currents) intended for it, and sends them along.
Each voice current impresses itself upon its own “carrier current” and passes over the common line; yet the voices never intermingle. Millions of dollars are thus saved in copper wire to carry separate voices.
SOME FACTS AND FIGURES
The telephone “talk tracks” of the nation measure approximately 33,200,000 miles of wire, 60 per cent of which are in underground cables. The copper in them weighs 700,000 tons; the overhead wires are strung on 30,200,000 poles. The wires in the underground cables along Broadway, New York city, if put on poles would require ten pole-lines, each as high as the Woolworth Building, with the cross arms two feet apart and ten wires to the cross arm.
The people of this country talk with one another at the rate of 18,250,000,000 completed telephone conversations per year in addition to 3,000,000,000 conversations originated but not completed. In New York during the busiest hour of the day, from 10 A. M. to II A. M., more than 450,000 calls, are originated and answered by the operators in the various exchanges of the city. In New York alone there are 950,000 telephones, and 3,341,000 miles of wire, weighing 65,000 tons.
The employees engaged in the telephone service of the metropolis would make a city of 28,300 population. About 4,000,000 directories are distributed to the public each year. These directories weigh 7,800 tons, and require an army of 500 men to do the work of distribution.
What the telephone means to the world no man can correctly gauge. It has established a miraculous communication. It has banished isolation. Ocean now sounds to ocean, and continent to continent. The business, political, and social life of the nation and of the world courses over the telephone circuits and spreads through the ether.
In less than a half-century the first feeble cry of the baby telephone grew into a voice which could be distinctly heard throughout the length and breadth of the nation.