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From the 1924 book, A Popular History of American Invention. Original chapter title, “SENDING MESSAGES AND PICTURES OVER A WIRE—THE STORY OF THE TELEGRAPH.”
EARLY in the nineteenth century a fifteen-year-old lad, the son of a London music-teacher, saved all his pennies until he was able to purchase a small, dry volume describing the electrical discoveries of the Italian, Alessandro Volta. The book was written in French, and the boy had to save more pennies in order to get a French-English dictionary.
Before long he was able to read of Volta’s experiments and, with the help of his elder brother, began to practice them. Copper plates for his home-made battery were absolutely necessary, and pennies were now very scarce. One day a happy inspiration caused him to make the copper pennies themselves serve the purpose, and his battery was in operation.
Such was the introduction to electrical science of Sir Charles Wheatstone, the inventor of the English telegraph. As a young man he had won distinction by his experiments with sound. By 1834 this work brought him an appointment to the chair of experimental physics in King’s College, London. Here he continued his experiments with sound; but his most important result at this time was his measurement of the velocity of an electric current.
At length there came to him in his laboratory an army officer home on furlough, William Fothergill Cooke, who was engaged on the invention of a telegraph. Cooke, lacking the scientific knowledge necessary to complete his invention, appealed to Wheatstone for assistance. Wheatstone also was experimenting with the telegraph, and the two entered into a partnership. It resulted in the invention of the five-needle telegraph in 1837.
The telegraph of Wheatstone and Cooke consisted, at the receiving end, of a loop of wire, within which was suspended a magnetic needle. By closing the circuit the needle could be deflected to the right or the left depending upon the direction in which the current flowed. Five separate circuits and needles, together with a sixth return circuit, were required. By 1845 Wheatstone had reduced his system to a single-wire circuit.
The repeated deflections of the needle were made to spell out words by pointing to letters on a dial. Although much inferior to the Morse telegraph—invented about the same time—Wheatstone’s system was used in England for many years.
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|Cooke and Wheatstone’s Five Needle Telegraph.|
As with other great inventions the attitude of the public toward the telegraph was cool; people regarded it as a new fangled complication. It required a dramatic incident to bring it into prominent notice, and although the story has frequently been told it is worth repeating.
Shortly after the telegraph had been installed over thirteen miles of the Great Western Railway, a mysterious death occurred in one of the outlying districts of London. A woman was found dead in her home. At an early hour of the same morning a man had been observed to leave the house and take the slow train for London. To affect a quick capture, some one thought of the telegraph, and immediately the operator telegraphed a description of the man to the police in London.
The murderer was dressed in the garb of a Quaker, but since the telegraph code contained no signal for the letter Q the operator began to spell the word “kwaker.” The London operator asked to have this repeated and continued to do so until a boy suggested that the whole message be sent. When this was done, its meaning at once became clear. The man was arrested as he stepped off the train and at his trial confessed to the crime. The incident quickened public interest; the value of the telegraph had been demonstrated.
HOW MORSE, THE ARTIST, BEGAN
It is surprising that the inventor of the modern telegraph was a well-known artist who had very little training in science. Samuel Findley Breese Morse, son of a Congregational minister, was born in 1791 at Charlestown, Mass., not far from the birth place of Benjamin Franklin. He came from sturdy Puritan ancestors and was educated at Andover and Yale.
At college Morse came under the influence of Professor Jeremiah Day, one of the foremost men of science of his time. Morse became interested in the experiment in electricity. We find in his notebooks this statement: “If the electric circuit be interrupted at any place the fluid will become visible.” Later Morse asserted that it was this “crude seed which took root in my mind, and grew into form, and ripened into the invention of the telegraph.”
At an early age Morse displayed a keen interest for painting. When a mere lad, he painted water-colors. In college he turned this ability to account by painting miniature portraits which he sold to his fellow students at five dollars apiece. Before leaving Yale in 1810 he completed a painting of the “Landing of the Pilgrims,” and at graduation decided to devote his life to art. To this end he became a pupil of Washington Allston, one of the best-known American painters of his day, and in 1811 sailed with him for England. In London he was admitted to the Royal Academy, and that brilliant artist, Benjamin West, advised and befriended him.
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|Samuel Morse Birthplace, Charlestown, Mass.|
Morse remained four years in England, making the acquaintance of some of the most notable men of his time and winning marked success in his chosen profession. During this time he won a gold medal for his work in sculpture and in 1813 exhibited at the Academy a huge “Dying Hercules,” which was classed among the best twelve paintings there. But he had already stayed abroad a year longer than his allotted time; his funds were gone, his clothes threadbare.
In 1815 he returned to America, where his fame had preceded him. The people of Boston flocked to see his work, and its cultured society gave him a most cordial welcome. But no one would buy his paintings, and poverty stared him in the face. Morse, supremely interested in the big things of art, was now compelled to eke out a scanty living by painting portraits.
After three miserable years in Boston, his uncle invited him to Charleston, South Carolina. There he succeeded as a portrait-painter and soon accumulated $3,000. With money in his pocket and many commissions, Morse went to Concord, New Hampshire, and married Lucretia Walker. He returned to Charleston, but eventually left for New York, where he and other artists founded the New York Drawing Association, of which organization he was elected president. This led, in 1826, to the National Academy of the Arts of Design.
Morse delivered lectures on “The Fine Arts,” and as president of the National Academy enjoyed considerable popularity. His father and mother and his wife had died, and, in 1829, Morse returned to Europe to spend three years in the art centres of Italy and France.
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|Painting by Morse. He was an accomplished artist.|
THEIDEA OF THE TELEGRAPH FLASHES UPON MORSE
For all his passion for art, Morse was destined to make his name in another direction and to throw his energy, heart, and soul into a work diametrically opposed to painting.
In 1832 he was returning from Europe on the packet ship Sully. In the cabin of the ship Doctor Charles T. Jackson, of Boston, exhibited an electromagnet which he had obtained in Paris. To the passengers, Jackson described some experiments which he had seen Ampere perform. Morse at once recalled his early studies in electricity and, upon inquiry, learned that Faraday considered the speed of electricity as instantaneous.
Totally ignorant of any previous work upon the subject and, indeed, of any other similar invention, Morse, with the insight of true genius, conceived the idea of the telegraph. Could an electrical mechanism be devised for transmitting signals and messages from a distance? Asking himself that important question, Morse was definitely launched upon a project which finally resulted in his invention of the modern telegraph.
Throughout the remainder of the long and tedious voyage Morse busied himself with plans for his great invention. The pages of his sketch-book were no longer utilized for artistic impressions; instead, crude drawings of telegraph instruments took their place.
One of the distinctive features of his proposed system was an automatic receiver for recording the messages. Already he had pictured in his mind an electromagnet with its armature, a moving tape, and a system of dots and dashes. His enthusiasm knew no bounds. As he landed in New York, he remarked to the captain: “Should you hear of the telegraph one of these days as the wonder of the world, remember that the discovery was made on board the good ship Sully.”
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|SKETCHES FROM MORSE’S NOTE-BOOK. Samuel F. B. Morse was a passenger on the packet-ship Sully which sailed from Havre on October 1, 1832, for New York. At dinner one evening he conversed with a Doctor Jackson on the transmission of electricity over a wire. A few days later he made rough drawings of an electric telegraph. These are not the drawings of his earliest instruments. They bear, however, a close resemblance to those which he exhibited on the packet-ship Sully. From “Life of S. B. Morse,” by S. I. Prime.|
The one great thought that now dominated every waking moment of Morse’s life was to perfect his telegraph. For three years he made little progress. Beset with poverty, having no fixed place of abode, very little scientific knowledge and less mechanical skill, the obstacles in his way seemed almost insurmountable.
In 1835 his renown as an artist gained him an appointment as professor of the literature of arts and design in the newly established University of New York. Here he came into close relationship with Leonard D. Gale, professor of chemistry. Gale gave him valuable assistance, especially in the making of batteries. But progress was slow.
Apparatus and supplies were exceedingly difficult to obtain in those days, and Morse was compelled to make his electromagnet himself. From a blacksmith-shop he obtained a soft iron core, bent to the shape of a horseshoe. Insulated copper wire was unknown, so he bought a few yards of bare wire and insulated it by methodically and painstakingly winding cotton around it.
One of his first disappointments was the discovery that the electric current in his line would not work the armature of the electromagnet. He had used only a few turns of rather coarse wire. But at this point Gale acquainted him with Professor Joseph Henry’s remarkable work in electromagnetism.
Henry had increased the sensitiveness of an electromagnet to a marvellous degree by using many turns of fine wire; indeed, he almost anticipated Morse in the invention of the telegraph.
In his laboratory at the Albany Normal School, Professor Henry had strung a mile of wire. At one end of the circuit he placed a battery and key and at the other an electromagnet. By pressing the key he caused the armature of the magnet to strike a gong and thus give signals by sound. Being a pure scientist, however, Henry was not interested in the practical development of his discovery.
After he had learned of Henry’s discoveries, Morse was able to correct the faults of his apparatus. Soon he had a crude model in operation in the laboratory of the university. The picture printed below shows its general form. Upon a wooden frame nailed to a table he mounted the electromagnet and clockwork to move the tape, and to the pendulum he attached both the armature of the magnet and the marking-pencil. When the circuit was made and broken by a special device, the pendulum swung back and forth so that its pencil marked the moving tape, and the “signals” were read off.
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|Morse’s original sending and receiving instruments. Above—facsimile of the original sketch, made by Morse, of the electric telegraph taken from his note-book.|
This was a great step forward; but new difficulties retarded the invention. It is impossible to send water through a pipe for miles without great pressure. It is equally impossible to send an electric current through a wire for miles without the pressure we now call “voltage.” In telegraphy weak currents were used, and in sending an electric signal through great lengths of wire, the effect at the end of the long wires was so feeble as to be practically imperceptible.
To overcome this defect Morse invented what is called a relay. If the invisible current would not actuate a heavy receiver, at least it could be made to operate a weak spring armature of a very sensitive electromagnet. A slight pull of the throttle of a powerful locomotive starts the wheels moving; a feeble current of electricity will affect the magnet of a relay in the same way. In a word, the relay acts like the throttle of a locomotive, and thus moves local electrical mechanism.
Morse now had all the elements of the modern telegraph. This was in 1837 and in that same year Congress directed the secretary of the treasury to inquire into the desirability of establishing a system of telegraphs in the United States. This action fired Morse with still greater enthusiasm, and he determined to bring his invention to the attention of the public. But, without funds and influence, he was helpless.
MORSE MEETS ALFRED VAIL
About this time Morse, while demonstrating his apparatus to some visitors, made the acquaintance of a young man named Alfred Vail, whose father, Judge Stephen Vail, was well known, prosperous, and the owner of the Speedwell Iron Works at Morristown, New Jersey. Young Vail immediately foresaw the tremendous commercial possibilities of the telegraph, and he suggested that Morse accept him as a partner in the enterprise.
This was the very assistance that Morse needed, and he was only too glad to grant the request; particularly as the elder Vail supplied $2,000 for additional experiments and offered his foundry as a workshop. Alfred Vail, possessing considerable mechanical ability, at once took off his coat and went to work with all the enthusiasm of youth. He made many improvements in Morse’s instruments and very largely worked out the Morse code of dots and dashes.
The ardor of Judge Vail, however, soon began to cool. Ridiculed by his acquaintances for the support that he had given to this rash scheme, he now regretted his generosity. But at last in January, 1838, the telegraph was complete. Vail summoned his father to the workshop and the judge wrote this message: “A patient waiter is no loser.” He asked his son to send it to Morse, who was at the receiver, stating that if he could do so he would be satisfied. The test was a complete success. The invention of the telegraph was achieved.
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|Stages In the Evolution of Morse’s Telegraph: First form of key(left). Improved form of key (right).|
THE WORK OF PUBLICITY
Often more difficult than perfecting a new invention is the task of properly introducing it to the public. So it was with the Morse telegraph. Skepticism had to be overcome, financial support secured, and the public educated to a realization of the value of the telegraph.
When placed on exhibition in New York and Philadelphia, no one seemed interested. As, later, they were to say of the telephone, the telegraph was only a “scientific toy.” But Morse’s patent was filed as a caveat at the United States Patent Office in 1837, and in December of the same year he appealed to Congress for aid to build an experimental line, pointing out that the chief purpose of his invention was the public welfare and not private gain.
He took his telegraph to Washington and finally succeeded in interesting the Committee on Commerce of the House of Representatives. The chairman of the committee, Francis O. J. Smith, resigned his seat in Congress in order to become an active partner in the enterprise. In 1842, a bill was introduced appropriating $30,000 for the building of an experimental line between Washington and Baltimore.
Morse now seemed to be on the flood-tide to success. A company was formed for the promotion of the enterprise, and Morse and Smith hurried away to Europe to secure patents in foreign capitals. But stormy days were ahead. Morse was entirely unsuccessful in his efforts abroad, and returning home he found Doctor Jackson claiming a share in his invention and Congress wholly indifferent to the passage of his bill.
To add to his difficulties, Morse faced the bitterest poverty. The Vails were unable to give him further assistance and his other associates left him to fight the battle alone.
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|Stages In the Evolution of Morse’s Telegraph: Early relay. The two keys and the relay are in the National Museum, Washington.|
In court, Morse proved the absolute falsity of Doctor Jackson’s claims, and by taking a few pupils in painting and charging them a small fee, managed to keep from starving. While in Paris he had learned from Louis Daguerre the new process of photography, and with Doctor John W. Draper of the university he was the first to introduce daguerreotypes in America. This, too, was unprofitable.
The following incident, told by General Strother of Virginia, one of his art pupils, describes the poverty of Morse during those dark days. Strother’s second quarter’s pay was due and his remittance from home had not arrived. One evening, Morse approached him and said courteously:
“‘Well, Strother, my boy, how are we off for money ?”
“Why, professor,” I answered, “I am sorry to say that I have been disappointed, but I expect a remittance next week.”
“Next week,” he repeated sadly, “I shall be dead by that time.”
“Dead Sir ?”
“Yes, dead by starvation.”
“I was distressed and astonished.” I said hurriedly: “Would ten dollars be of any service ?”
“Ten dollars would save my life. That is all it would do.”
“I paid the money, all that I had, and we dined together. It was a modest meal, but good, and after he had finished, he said:
“This is my first meal for twenty-four hours. Strother, don’t be an artist. It means beggary. Your life depends upon people who know nothing of your art and care nothing for you. A house dog lives better, and the very sensitiveness that stimulates an artist to work keeps him alive to suffering.”
At length, February 23, 1843, Morse’s bill for an appropriation of $30,000 was again introduced in Congress. The project suffered the severest ridicule. Many members regarded it as the visionary scheme of a “crank” and were afraid to go on record as even favoring it. Defeat seemed certain.
But the bill did pass the House by a narrow margin of eight votes, and it went to the Senate. On the last night of the session, Morse anxiously waited in the gallery. One of the senators came up to him and declared: “There is no use of your staying here. The Senate is not in sympathy with your project. I advise you to go home and think no more about it.”
Broken in spirit, dejected, his last hope shattered, Morse returned to his boarding-house, and, after paying his bill and buying a ticket to New York, all the money he had to his name was thirty-seven and a half cents. But the next morning while he was at breakfast he received a visit from a young lady. Coming toward him with a smile, she exclaimed:
“I have come to congratulate you.”
“What for, my dear friend ?” asked the professor of the young lady, who was Miss Annie G. Ellsworth, daughter of his friend the commissioner of patents.
“On the passage of your bill.”
The professor assured her it was not possible, as he remained in the senate-chamber until nearly midnight, and it was not reached. She then informed him that her father was present until the close, and, in the last moments of the session, the bill was passed without debate or revision.
Professor Morse was overcome by the intelligence, so joyful and unexpected, and gave at the moment to his young friend, the bearer of these good tidings, the promise that she should send the first message over the first line of telegraph that was opened.
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|Stages In the Evolution of Morse’s Telegraph: First Washington-Baltimore instrument. The Washington-Baltimore instrument is owned by Cornell University.|
|Stages In the Evolution of Morse’s Telegraph: Enlarged view of Morse Regular, used on the first Washington-Baltimore line.|
“WHAT HATH GOD WROUGHT ?”
Morse and his partners now took up the work of construction. Ignorant of the difficulties confronting them, they unfortunately decided in favor of underground wires. After they had exhausted more than two-thirds of the appropriation, the insulation proved defective and the underground system had to be abandoned. Luckily, Ezra Cornell, later to be the founder of a great university, was associated with them. Upon his advice they hurriedly strung the wires overhead, insulating them by the necks of bottles thrust through holes bored in the tops of poles. This saved the situation.
On the day chosen for the public exhibition, May 24, 1844, Annie Ellsworth handed to Morse, sitting at the transmitter in the Supreme Court room of the capitol, the words: “What hath God wrought ?“ This was immediately transmitted to Vail in Baltimore, who in a few moments sent back the same message, and the invention of the telegraph passed into history.
|The first message sent by Morse. “What hath God wrought.”|
The public’s interest remained lukewarm. As with Wheatstone and his English telegraph, something sensational was needed to bring the new invention into prominent notice and favor. It so happened that the national Democratic convention was then in session at Baltimore. Vail learned that Silas Wright, of New York, had been nominated for the vice-presidency, and telegraphed the news to Washington.
Morse received and handed the telegram to Wright, who was in the senate-chamber. Wright declined the nomination, and Morse instantly telegraphed back his refusal. The members of the Baltimore convention, on being handed the despatch, would not believe, and they adjourned until a committee was sent to Washington to report truthfully on the matter. Complete verification of the telegraphic message convinced the American people of the immense importance of telegraph service.
Morse offered his invention to the government for $100,000, but although they voted $8,000 for maintaining the original telegraph line, they declined to commit themselves further. Disappointed, Morse then organized the Magnetic Telegraph Company and set about securing funds for the construction of a line from New York to Philadelphia. It was slow but sure work.
Little by little telegraph lines began to multiply. They spread like a network over the Eastern States. Many companies sprang up. Morse’s patents were infringed and he was compelled to file many lawsuits for his rights, which the courts always upheld. There was plenty of telegraph business now, yet no one seemed to be making money in it.
In 1856, Hiram Sibley organized the Western Union Telegraph Company, which some one likened to “collecting all the paupers in the State and arranging them into a union so as to make rich men of them.” The company succeeded, and a line was put through to the Pacific coast. The profits were enormous, and through his patents Morse became a wealthy man. He was honored with orders, decorations, and medals by the leading nations of the world. He died in 1872, full of years and rich in the esteem of his fellow men.
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|Early telegraph operator.|
It was early discovered that messages could be read simply by listening to instead of seeing the clicking of the armature of the electromagnet. Morse had considered the automatic recording device of his receiver the most important feature of his invention. Yet reading by sound was so much simpler and easier that neither threats nor penalties could prevent the practice. Vail then devised the modern type of sounder, and also made many other changes in telegraph apparatus.
The first great improvement was made in 1858 by J. B. Stearns, of Boston. In that year he introduced duplex telegraphy; a system by which two messages, one in each direction, might be sent over a single wire at the same time. This he accomplished by arranging relays at each end of the line which would, in each case, respond to incoming signals, but not to outgoing signals. In that way a message could be received and another sent, at the same time over the same wire.
EDISON AND THE TELEGRAPH
One of the “brass pounders” to whom Morse’s invention gave employment was Thomas A. Edison. A telegraph operator with his extraordinary inventive gifts would naturally introduce improvements. One of his earliest inventions was a duplex telegraph of his own.
In 1869 he went from Boston to New York. Arriving there he borrowed a dollar to tide him over until he could get a position as an operator. While waiting he spent much of his time about the offices of the Gold Indicator Company in order to study their complicated system of indicators and transmitters for distributing to the various brokers’ offices of the city, the current stock quotations.
Edison had been waiting for three days, when an opportunity occurred to test his genius. As usual, he was sitting in the company’s office, when suddenly the complicated mechanism which controlled the outgoing lines came to a dead stop. Soon more than 300 boys, one from every broker’s office on the street, came crowding into the room. Pandemonium reigned and the man in charge lost his head. Edison quietly walked over to the instrument, studied its parts for a moment, and located the trouble. A contact spring had broken off and fallen between two gear-wheels, thus stopping the movement.
Doctor Laws, the superintendent of the company, arrived and asked the foreman what was the cause of the trouble; but the man was unable to explain. Edison then volunteered to fix the instrument, and was told to do so at once. Seemingly by magic, he deftly removed the spring, adjusted it, and set the wheels moving again.
Doctor Laws called Edison into his office and offered to put him in charge of the “tickers” at $300 a month. Almost overcome with astonishment and delight, Edison accepted the position. To one who just lately had been compelled to borrow a dollar, the salary of $300 a month was princely; but Edison, instead of taking it easy, worked no less than twenty hours a day trying to improve the stock-tickers of that time.
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A stock-ticker is a telegraph instrument which automatically records on a moving tape, the quotations of the various stocks listed on the exchange as rapidly as they appear. A man in the exchange sits at a keyboard, circular in form and carrying upon it all of the letters and figures used in stock quotations. As he reads the quotations, he perforates a moving tape by striking the keys just as in operating a typewriter. This tape passes through a transmitter which operates a large number of line relays and sends the signals to the tickers in the brokers’ offices, and also to distant cities.
After Edison had taken out patents on a large number of inventions covering improvements on the tickers, General Lefferts, the president of the Gold and Stock Telegraph Company, offered to buy his patents. Edison had intended to ask $5,000 and, if necessary, to come down to $3,000.
But, when the psychological moment arrived, he did not have the nerve to name such a large sum, so he asked Lefferts to make him an offer. The president of the telegraph company suggested the sum of $40,000. “This caused me,” said Edison, “to come as near fainting as I ever got. I managed to say that I thought it was fair.” After that he opened laboratories in Newark.
EDISON SENDS FOUR MESSAGES AT A TIME OVER THE SAME WIRE
Edison soon became involved in a multitude of inventions, but one of his chief problems was an automatic and multiplex telegraphy. George Little, an Englishman, had invented a system of automatic telegraphy which worked well on short lines but did not meet the exacting requirements of long-distance telegraphy.
Accepting Little’s principle of mechanism, Edison converted it into a highly satisfactory system. In a short time he was sending and recording 1,000 words per minute between New York and Washington, and 3,500 words to Philadelphia.
Like many other automatic systems, it included a hand-punch for perforating a moving tape which was passed through an automatic transmitter. Wherever a hole came in the tape an electric contact was made, and an “impulse” sent to the line. At the receiving end an automatic recorder printed the message on chemically prepared paper. Edison improved every part of the system, and for some time it was in active use on American lines.
Then came Edison’s quadruplex telegraphy, which enabled him to send over a single wire four messages at the same time, two in each direction. In this system Edison combined two sets of instruments. One set would respond only to a change in the strength of the line current, while the other set would respond only to a change in the direction of the current.
Although this system was sensitive to bad weather conditions and was so delicately balanced as to be easily thrown out of adjustment, yet it was of immense importance in extending telegraph service. It has been estimated that in America alone quadruplex telegraphy has accomplished a saving of from $15,000,000 to $20,000,000 in line construction.
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|Duplex system of Telegraphing.|
TYPEWRITING BY TELEGRAPH
As early as 1846 Alexander Bain, a Scotchman, invented an automatic transmitter employing a perforated strip of paper. At the receiving end the dots and dashes were recorded on a rapidly moving tape of chemically prepared paper by means of an iron stylus.
The first real printing telegraph, one which actually printed the message in Roman type, was invented by David E. Hughes, of Kentucky, in 1855. Hughes was a master of music and a born inventor. His ambition was to invent a telegraphic type printer. Before he could accomplish such a thing it was necessary to keep his transmitting and receiving instruments in perfect unison with each other. For a long time this had baffled him.
Finally, two darning-needles borrowed from an old lady in the house where he lived gave him the clue. He arranged a system of equally timed vibrating needles or rods, and in this way solved his problem. Hughes’s printing telegraph was used for a time in this country, but was gradually superseded by other systems. In England and Europe it still has a very wide application.
Professor Henry A. Rowland, of Johns Hopkins University, invented a printing telegraph which could send eight messages simultaneously over a single wire. It was a beautiful piece of work, but unfortunately was not adapted to the electric requirements of existing lines. It embodied, however, a principle which has been frequently utilized in other systems.
The transmitter consisted of a keyboard, like a typewriter, and the recording instrument printed the message exactly as a typewriter does. The recorder, too, was under the perfect control of the transmitting operator. The pressing of any key sends an “impulse” over the line which automatically prints on a sheet of paper the corresponding letter. As in the ordinary office typewriter, the telegraph operator also spaces, makes numerals, and shifts the carriage in either direction and from line to line. These features have now become standard in many systems.
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|Modern automatic tape transmitter.|
Other men who have invented widely used systems more or less similar to those already described are Baudot, Buckingham, Murray, and Delany. The most remarkable system is the Pollak-Virag telegraph. A tape is punched with a double row of holes and passed through a transmitter in the usual way.
The impulses sent over the line are made to operate a delicately hung mirror which can swing in every direction. Upon this mirror is thrown a beam of light from an incandescent lamp. As the mirror swings, the beam is reflected to a sensitized sheet of paper. Thus the signals in the form of light are actually photographed. In its latest form, this telegraph has been made to record its messages in legible writing. The speed of transmission is over 100,000 words an hour. It is impossible to predict the future of such an instrument.
THE MODERN MULTIPLEX
The multiplex system now in use on the Western Union lines sends eight messages on a single line at the same time, and prints them in typewritten form ready for distribution. Four messages are sent in each direction, and eight operators are required at each end of the line, four to send and four to receive. This system is an adaptation of the Delany multiplex.
As you enter a large Western Union Telegraph office you see row after row of these machines in operation. The click-click of the transmitters mingling with the hum of vibrating tuning-forks and rotating motors is almost orchestral. To and fro, from city to city, nation to nation, shuffle messages. All are important; the very purpose of the telegraph is to save time.
Four strips of moving tape are perforated by operators at typewriter keyboards, after which the strips pass through the respective transmitters. The electric “impulses” are sent to the line through the segments of a rotating metal disk, over which moves a conducting arm or brush. There are twenty of these insulated segments, five for each transmitter, and at each rotation one letter is sent to the line from each instrument.
At the receiving end of the line there is another disk exactly similar to the first and rotating in exact unison with it. Therefore, as the impulse from a particular transmitter is sent to the line, the corresponding receiving instrument is at that same instant also in connection with the line.
These four impulses are sent to the line in rapid succession and received at the other end in perfect sequence. As already stated, four messages are also being sent from the opposite direction at the same time. The speeds of the motors which operate the rotating disks are controlled by vibrating tuning-forks of exactly the same pitch.
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|A Page Multiplex Printer.|
Since each operator can send from forty to fifty words a minute, the maximum speed for eight is from 320 to 400 words. The actual speed of the automatic systems depends upon and is limited by the speed with which an operator can perforate a tape. High speeds are obtained only when the tape has been prepared in advance by a large number of operators. There are mechanisms for very rapid sending and receiving, but as yet there is no magic method of preparing the tape.
Very recently, as described in the chapter on the telephone, it has been made possible to send as many as forty telegraph messages over a single wire at the same time. This system is adapted only to long-distance transmission and has not yet come into extensive use. There is no doubt, however, that it holds great promise for the telegraph service of the future.
|Automatic Telegraph Printer at receiving end.|
ELISHA GRAY INVENTS HIS HARMONIC TELEGRAPH
One of the most interesting figures in telegraph history is Elisha Gray. Of Quaker parentage, educated at Oberlin College, with a genius for invention coupled with marked mechanical ability, he early turned his attention in life to electricity. Gray became one of the original promoters of the Western Electric Company and from his many inventions amassed a fortune. Many of these were telegraphic devices.
His most interesting invention was the harmonic telegraph. At the sending end Gray placed a number of electromagnets, each one of which kept in constant vibration a tuning-fork of definite pitch. These vibrating tuning-forks, each of a different pitch, were made to interrupt the line current and therefore sent out a complex combination of impulses.
At the receiving end, the line current was passed about an equal number of electromagnets, over each of which was placed a steel reed. Each reed was so tuned that it would respond and be thrown into vibration by one and only one of the forks at the transmitting end.
Therefore, Morse signals sent through the contact points of any one of the vibrating forks were received only in that circuit whose reed vibrated at the same rate. Gray sent as many as nine messages over a single wire. The system has been since improved so that it sends twelve.
Gray’s “telautograph” was one of the first of the facsimile telegraphs. He made a pencil in the hand of the sender electrically operate another pencil at a distance and, therefore, reproduce handwriting.
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|Modern Chicago switchboard, Western Union office.|
TELEGRAPHING PICTURES OVER WIRES
Although the art of telegraphing pictures is still in the experimental stage, very remarkable results have been obtained. The first successful long-distance photographs were made by Professor Arthur Korn, of Germany, in 1904. Professor Korn took advantage of the fact that the element selenium is electrically sensitive to light, and that its resistance changes with a variation in the intensity of illumination.
Within a glass cylinder, which can both rotate and shift itself in the direction of its length, glows an electric lamp. Around the cylinder is wrapped the photograph about to be transmitted. It is evident that the rays from the lamp will easily pass through the light portions of the photograph, but not so easily through the dark. By rotating and by shifting the cylinder in the direction of its length, the rays from the lamp will strike every portion of the photograph in its spiral path.
The beam from the lamp, of course, passes through only one spot at a time. If that spot is comparatively light or transparent, the beam passes through the revolving cylinder and falls upon the selenium cell. Since selenium varies in conductivity with the amount of light that happens to fall upon it at any given time, the amount of current which passes through an electric circuit in which the selenium is included also varies.
At the receiving end is another rotating and shifting cylinder around which a photographic film is wrapped. The electric current is made to open and close a shutter through which the beam of light is focused upon the revolving cylinder. The operation is clear enough. The selenium cell of the sending instrument is now in the dark, now in the light, depending upon the resistance offered to the beam of light by the different portions of the photograph wrapped around the transmitting cylinder.
The current in the line fluctuates with the amount of light that happens to fall upon the selenium cell at any given instant. These fluctuations in turn cause the shutter at the receiving end to open or close, so that more or less light falls upon the rotating or shifting revolving cylinder.
Hence the beam of light at the receiving end traces a spiral record on the film, but a record which is now black and now light. Develop the photograph of the receiving cylinder and it is now a duplicate, composed of fine lines, close together, of the picture wrapped about the transmitting cylinder.
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|CLEVELAND’S HIGH BRIDGE. A picture transmitted by wire from Cleveland, Ohio, to New York, on May 19, 1924, by the American Telephone and Telegraph Company. A beam of light passes through a transparent rotating print and, falling upon a photoelectric cell, controls the amplitude of the line current. The line current in turn operates a specially constructed receiving element, the beam from which is recorded on a sensitive film rotating synchronously with the transmitting print.|
|EDITOR’S NOTE: This is a small portion of the picture. The vertical scan lines which are a result of the process do not show up in the reduced picture size digitized from the book.|
In Paris, M. Bélin experimented for a number of years with a different system. He produced a negative in relief which he wrapped about a revolving cylinder over which moved a stylus. The stylus varied the electric current in the receiving circuit with the light and shade of the picture. By a suitable mechanism, Bélin made this changing current vary the intensity of light thrown on the receiving film.
A theoretically old but only recently applied scheme is the one by which photographs are telegraphed in code. Over the print is placed a transparent sheet of celluloid, marked off in quarter-inch squares. The light and shade of the print is then carefully indicated on these squares by a system of code numbers which are telegraphed to the distant newspaper-office. From this code a black-and-white reproduction of the picture is quickly made for newspaper use.
Pictures of the Dempsey-Carpentier fight of July 2, 1921, were thus sent to Los Angeles to be reproduced the following morning: fifty minutes were consumed in telegraphing and an hour and ten minutes in decoding. The same pictures were also cabled to London, and reproduced soon after the event.
CYRUS FIELD AND THE ATLANTIC CABLE
Magnificent as the triumph of land telegraphy had been, it was destined to be outdone in the telegraphic conquest of the sea. To the clearness of vision and indomitable perseverance of that little group of pioneers who, against every obstacle of fate and man, accomplished the Herculean task of laying the first Atlantic cable, the world owes a debt of gratitude it can never pay.
In 1842, the first cable line in America was laid beneath New York Harbor by Morse during those anxious days of waiting for the recognition of his great invention. Another was laid between New York City and Fort Lee in 1845 by Ezra Cornell. In 1850 John Watkins Brett laid the first successful cable across the English Channel.
Two years later England and Ireland were connected by cable and, soon after, a cable was laid beneath the North Sea to Holland. Morse, even before he had perfected his original telegraph, with prophetic vision, predicted that some day men would telegraph beneath the Atlantic.
In 1852, an engineer named F. N. Gisborne conceived the idea of connecting by telegraph New York and St. John’s, Newfoundland. By this, the time of communication between the two continents was to be shortened by two days. Part of the line was to consist of a submarine cable across the Gulf of St. Lawrence.
Running out of funds, he applied to Cyrus W. Field, a retired merchant of New York, for financial assistance. Although Field had amassed a fortune, he was still a young man, and the project strongly appealed to him. It soon occurred to Field that of far greater importance to commerce was a direct cable joining the Old World with the New; in other words, a cable under the Atlantic. It became Field’s great obsession. Seldom has any man been fired with a more contagious enthusiasm or a mightier determination.
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|Cyrus Field would never give up.|
He began work immediately. The British and American Governments responded to his appeal for assistance, and vessels from each navy were detailed to make soundings of the ocean bottom between Newfoundland and Ireland. The report was exceedingly favorable, and Morse pronounced the project entirely feasible.
Sailing for England, Field organized the Atlantic Telegraph Company, and set about securing financial support. A quarter of the capital he supplied himself and had no difficulty in obtaining the rest. He then enlisted the services of Charles T. Bright, a young Englishman, as engineer for the company; but even more important was the addition of Professor William Thomson (afterward Lord Kelvin) of Glasgow University as an enthusiastic member of the enterprise.
The next step was to manufacture the cable. Although the distance to be covered was but 1,640 nautical miles, 2,500 miles of cable were supplied. It consisted of seven copper wires insulated with the newly discovered gutta-percha, wound about with tarred hemp, the whole sheathed in a casing of heavy iron wires.
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|Section of the Atlantic Cable, carried by Adams & Company’s Express wagon through the streets of New York. From Valentine’s Manual.|
To lay the cable England loaned the Agamemnon, and the United States the Niagara, two of the largest warships then afloat. On August 5, 1857, the two vessels, accompanied by an escort of several smaller ones, steamed away from the Irish coast amid much ceremony and with high hopes for success. For a time all went well. The paying-out machinery on the Niagara worked without a hitch.
Nearly 400 miles of cable had been laid down. Then, as the stern of the Niagara was lifted on a high wave, the cable parted, and could not be recovered. It was terribly disheartening. There was nothing to do but return to port and abandon the enterprise, at least for that year.
|The Niagara, Valorous, Gorgon and Agamemnon laying the Atlantic Cable at mid-ocean. From Valentine’s Manual.|
A half-million dollars had been lost, and many now believed the task impossible, but a second attempt was made in the following June. Improved paying-out machinery was installed, also a device for automatically releasing the cable if the strain became too great. This time the departure from Plymouth was made without ceremony. It was decided that the ships should proceed to mid-ocean, splice the cable, and lay it down in opposite directions.
On the way out the fleet encountered a terrific storm. It was so severe and lasted for more than a week that, day after day, it seemed as if nothing could save the Agamemnon and her precious cargo from being sent to the bottom. At length the fury of the gale spent itself, and the ships met in safety at the appointed spot. The cable was spliced and the machinery began to pay it out.
When scarcely three miles had been laid the cable parted The ships returned, re-spliced the cable and made a new start. But at a distance of fifty miles, without warning, the cable again broke.
For the third time the gallant ships returned to the rendezvous, and another splice was made. They proceeded very carefully. About 200 miles of cable had been laid. Optimism was running high. Every member of the enterprise felt that, at last, success would crown their efforts. Then, without apparent cause, the cable snapped twenty feet behind the Agamemnon.
Many of the stockholders were now in favor of abandoning the project; but the counsel of Field and Thomson prevailed, and it was decided to make a third attempt immediately. It was destined to succeed. Although the precious cable was threatened by icebergs and, in one instance, by a whale which grazed it in passing, the Niagara landed her end in Trinity Bay, Newfoundland, August 5, 1858, and on the same day the Agamemnon landed hers in Valentia Harbor.
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|Landing of the shore end of the Atlantic Cable at Trinity Bay, August 4, 1858. From Valentine’s Manual.|
All through, telegraph communication had been maintained from ship to ship, and now for the first time in history messages were cabled from coast to coast. Queen Victoria and President Buchanan exchanged greetings. On either ocean side the promoters were regarded as heroes, and honors were heaped upon them.
But in the midst of these celebrations, when the cable was scarcely a month old, the last message passed over it. Ignorance on the part of the electrician in charge of the electrical requirements of cable transmission resulted in the use of too high voltages, and the insulation had been ruined.
THE GREAT EASTERN IS CHARTERED FOR CABLE WORK
Undaunted, Field still persisted. However, with the Civil War approaching at home, and the numerous disasters fresh in the public mind, he took no part in the project for a number of years. In 1865, however, he organized another company, the necessary capital again being mostly raised in England, and chartered the famous Great Eastern, a mammoth ship too large for the commerce of that day.
The expedition sailed from Valentia Bay in July of that year, and succeeded without mishap in covering nearly two-thirds of the distance, when the Great Eastern’s machinery broke down. As she was tossed by the waves, the cable parted and was lost. Surely fate seemed against the undertaking.
|An old print illustrating the arrival of the Great Eastern, carrying the Atlantic Cable, in Newfoundland, July 27, 1866.|
A man of less steadfast faith and courage would have given up. But Field’s purpose was unshakable. A new company was organized and on July 13, 1866, the Great Eastern started on her second venture. This time it was crowned with success, and in just two weeks the cable was safely landed on the Newfoundland shore.
From that day to this the world has never been without transatlantic cable service. With little delay the Great Eastern sailed back to recover the lost cable of the previous year. After hooking the cable twenty-nine times, and as often losing it, the thirtieth effort brought it to the surface. It was spliced with new cable and carried in safety to the cable station at Heart’s Content, Newfoundland.
Cyrus W. Field, after years of disappointment, had finally succeeded. It was an achievement worthy of monumental honors. Thanks to his patient determination, submarine cables now bind together in friendly intercourse the Old World and the New.
|Section of the Atlantic Cable of 1866.|
INSTRUMENTS USED IN SUBMARINE CABLING
The mechanics of submarine telegraphy are much more complicated than are those on land. A long cable has its metallic core, insulating sheath, and the salt water outside acts like a huge Leyden jar or condenser. The current flowing in the core induces, in the water, opposing currents which enormously retard the speed of transmission.
Furthermore, the currents are very weak. This is necessary because of the great resistance of such a long conductor, and the fact that only comparatively small voltages—not over eighty volts—can be used.
In one sense the success of submarine telegraphy really depended upon the ability to devise an instrument delicate enough to detect these feeble currents. It was accomplished by Sir William Thomson’s mirror galvanometer.
This instrument is essentially the same as our very sensitive spot-light galvanometers of to-day. The current from the cable was passed through a coil of many turns of fine, silk-covered wire. In the heart of the coil in a little air-chamber, suspended by a delicate fibre of silk floss, was a small round mirror.
On the back of the mirror were four tiny magnets. The magnetic field from the currents in the coil caused the tiny magnets to turn the mirror one way or the other, depending upon the direction of the current. Upon the mirror was focused a beam of light which, in turn, was reflected to a white screen.
As the mirror rotated with the changing cable currents, this beam of light moved back and forth on the screen tracing out the dots and dashes of the code. In cable transmission, positive and negative currents are alternately sent to the line; that is, the cable current is constantly reversed. A deflection in one direction means a dot and in the other a dash.
So delicate a recording instrument is the mirror galvanometer that the feeblest currents will operate it. When the first two Atlantic cables had been successfully laid they were connected together at Newfoundland and the current from a tiny cell, consisting of a lady’s silver thimble, a bit of zinc, and a few drops of sulphuric acid, sent through them. Even the signals from this infinitesimal current traversed the ocean twice, and were successfully received by the mirror galvanometer.
But, though this was a remarkable invention, it did not record the message. Again Sir William Thomson was equal to the emergency and met it with the siphon recorder. The feeble cable currents would not operate heavy sounders nor any of the printing devices used on land lines. Whatever was to be the recording device, it must require but very slight energy to set it in motion.
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|Keyboard perforator of a cable office.|
|Siphon recorder that receives the message.|
Just as its name indicates, in this second invention Sir William Thomson used a real ink-carrying siphon to record the message. The cable currents passed through a coil of very fine wire, delicately suspended between the poles of a strong permanent steel magnet.
By means of slender filaments the motion of this coil was communicated to the long arm of a fine glass siphon. The short arm of the siphon dipped into a reservoir of ink and the other end glided back and forth across a strip of moving tape. Thus, as the currents corresponding to the dots and dashes deflected the coil first in one direction and then the other, the record was written on the tape in a characteristic wavy line.
Cables are the arteries of international communication. Seventeen of them pass beneath the Atlantic. Two cross the Pacific. They thread the Mediterranean and the Red Sea to India and the Far East. They creep beneath the arms of the seven seas, and skirt the continents.
In all, this small planet boasts, approximately, 1,800 government and privately owned submarine cables, measuring nearly a quarter of a million nautical miles. Over them pass 40,000 cablegrams a day. They bring the remote regions of the earth into contact with the great centres of life and commerce.
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|Forward cable machinery, U. S. Cable Ship Burnside. Courtesy U. S. Signal Corps.|
|Landing shore end of cable from Burnside, Philippine Islands. Courtesy U. S. Signal Corps.|