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Nature's Miracles Volume 3: Electricity and Magnetism

<h2>CHAPTER X.</h2> <h3>THE ELECTRIC TELEGRAPH.</h3> In the year 1617 Strada, an Italian Jesuit, proposed to telegraph news without wires by means of two sympathetic needles made of loadstone so balanced that when one was turned the other would turn with it. Each needle was to have a dial with the letters on it. This would have been very nice if it had only worked, but it was not based on any known law of nature. Many attempts at telegraphing with electricity were made by different people during the eighteenth century. About 1748 Franklin succeeded in firing spirits by means of a wire across the Schuylkill River, using, as all the other experimenters had done, frictional electricity. In 1753 an anonymous letter was written to Scott's Magazine describing a method by which it was possible to communicate at a distance by electricity. The writer proposed the use of a wire for each letter of the alphabet, that should terminate in pith balls at the receiving end, and under the balls were to be strips of paper corresponding to the letters of the alphabet. The message was to be sent by discharging static electricity through the wire corresponding to the first letter of a word when the paper would be attracted to the pith ball and read by the observer. Then the wire corresponding to the second letter of the word was to be charged in like manner, and so on till the whole message was spelled out. This was the first practical (i.e., possible) suggestion for a telegraph. The writer also proposed to have the wires strung on insulators, which was a great advance over the other attempts. The communication was anonymous, as no doubt, like many others, the author feared the ridicule of his neighbors. It requires a vast amount of moral courage to stand up before the world and openly advocate some new theory that has never come within the experience of any one before. It requires much now, but it required more then; for a man in those days would have been roasted for what in these days he would be toasted. The rank and file of humanity have been opposed to innovations in all ages, but no progress could have been made without innovations. There always has to be a first time. Galileo is said to have been forced to retract, on his knees, some theory he advanced about the motion of the earth, and its relation to the sun and other heavenly bodies. Notwithstanding this retraction the seed-thought sown by Galileo took root in other minds, which led to the triumph of scientific truth over religious fanaticism. The writer in Scott's Magazine did not have the opportunity to put his ideas into practice, so the glory of the invention fell to others. Such men as this unknown writer are made of finer stuff, and they stand alone on the frontier of progress. They do not fear the bullets of an enemy half so much as the gibes of a friend. Much of their work is done quietly and without notice, and when something of real importance is worked out theoretically and experimentally, some one seizes upon it and proclaims it from the housetops and attaches to it his name; but perhaps years after the real inventor (the man who taught the so-called inventor how to do it) is dead, some one writes a book that reveals the truth, and then the hero-loving people erect a monument to his memory. Such a man was our own Professor Joseph Henry, so long the presiding genius at the Smithsonian Institution at Washington. He worked out all the problems of the present American telegraphic system and demonstrated it practically. Everything that made the so-called Morse telegraph a success had long before been described and demonstrated by Henry. Yet with the modest grace that was ingrained in the man he yielded all to the one who was instrumental in constructing the first telegraph line between Baltimore and Washington. Great credit is due to such men as Morse and Cyrus W. Field—neither of them inventors, but promoters of great systems of communication that are of unspeakable benefit to mankind. Henry pointed out the way, and Morse carried it into effect. Morse has had no more credit than was due him, but has Henry had as much as is due him? No great invention was ever yet the work, wholly, of one man. We Americans are too apt to forget this. I shall always remember Henry as a most unassuming, kindly, genial man, and I shall never forget his kindness to me. In 1874 I began my researches in telephony, having applied for a patent for an apparatus for transmitting musical tones telegraphically. This consisted of a means of transmitting musical tones through a wire and reproducing them on a metal plate (stretched on the body of a violin to give it resonance) by rubbing the plate with the hand—the latter being a part of the circuit. The examiner refused the application at first on the ground that the inventor or operator could not be a part of his machine. I took my apparatus and went to Washington, first calling upon Professor Henry, never having met him before. He received me most kindly, and allowed me to string wires from room to room in the institute, and when he had witnessed the experiments he seemed as delighted as a child. I now brought the patent office official over to the Smithsonian and soon convinced him that the inventor could be a part of his own machine. The same year I went abroad, and Henry gave me a letter to Tyndall. It was very fortunate for me that he did, for Tyndall was very shy at first, and it was only Henry's letter that gave me a hearing for a moment. The history of the few days that followed this first interview with Tyndall at the Royal Institution would make very interesting reading, if I felt at liberty to publish it. Suffice it to say that he was convinced in a few minutes after he had reached the experimental stage that not all my work had been anticipated by Wheatstone, as he asserted before seeing the experiments. Wheatstone had transmitted the tones of a piano, mechanically, from one room to another by a wooden rod placed upon the sound-board and terminating in another room in contact with another sound-board. But this was very different from transmitting musical tones and melodies from one city to another through a wire, as I could do with my electrotelephonic apparatus. It is a curious fact that the world is divided into two great classes, leaders and followers. Or we might say, originators and copyists; the former division being very small, while the latter is very large. As late as 1820 the European philosophers were trying to construct a telegraphic system based upon two ideas, announced a long time before, to wit, the use of static or frictional electricity, and a wire for every letter. It does not seem to have occurred to any one to devise a code consisting of motions differently related as to time, and to use simply one wire. In 1819 Oersted discovered the effect of a galvanic current on a magnetic needle, and published a pamphlet concerning his discovery. This stimulated others, and Ampère applied it to the galvanometer the same year. Arago applied it to soft iron, and here was the germ of the electromagnet. We see that as far back as 1820 we had the galvanic battery and the electromagnet, the two great essentials of the modern telegraph. However, there remained another great discovery to be made before these elements could be utilized for telegraphic purposes. One cell of battery was used, and the magnet was made by winding one layer of wire spirally around the iron, so that each spiral was out of touch with its neighbor. Barlow of England, a Fellow of the Royal Society, tried the effect of a current through a wire 200 feet long, and found that the power was so diminished that he was discouraged, and in a paper gave it as his opinion that galvanism was of no use for telegraphing at a distance. This paper stimulated others, and it was reserved for our own Joseph Henry, already referred to, to show not only how to construct a magnet for long-distance telegraphy, but also how to adapt the battery to the distance. He showed us that by insulating the wire and using several layers of whirls, instead of one, and by using enough cells of battery coupled up in series to get more voltage, as we now express it, it was possible to transmit signals to a distance. He not only set forth the theory, but he constructed a line of bell-wire 1060 feet long and worked his magnet by making the armature strike a bell for the signals, which is the basis of the modern "sounder." Nothing was needed but to construct a line and devise a code to be read by sound, to have practically our modern Morse telegraph. This line was constructed in 1831. In 1835 Henry, who was then at Princeton, constructed a line and worked it as it is to-day worked, with a relay and local circuit, so that at that period all the problems had been worked out. But, like the speaking-telephone in its early inception, no one appreciated its real importance. Henry himself did not think it worth while to take out a patent. Two years later the Secretary of the Treasury sent out a circular letter of inquiry to know if some system of telegraphic communication could not be devised. The learned heads of the Franklin Institute of Philadelphia, the oldest scientific society in America, advised that a semaphore system be established between New York and Washington, consisting of forty towers with swinging arms, the same as used in the days of Wellington. Among other replies to the circular letter of the secretary was one from Samuel F. B. Morse. Morse was not a scientist or even an inventor, at least not at that time. He was an artist of some note. In 1832, while crossing the ocean, Morse, in connection with one Dr. Jackson of Boston, devised a code of telegraphic signs intended to be used in a chemical telegraph system. Some years later Morse adapted Henry's signal-instrument to a recorder, called the Morse register, and this was the instrument used in the early days of the Morse telegraph. What Morse seems to have really invented was the register, which made embossed marks on a strip of paper, and the code of dots and dashes representing letters, now known as the Morse alphabet, although this latter is questioned. Morse took his apparatus to Washington and exhibited it to the members of Congress in the year 1838, but it was four years before a bill was passed that enabled him to try the experiment between Baltimore and Washington. We will let him describe in his own words the closing day of Congress. He says: "My bill had indeed passed the House of Representatives and it was on the calendar of the Senate, but the evening of the last day had commenced with more than 100 bills to be considered and passed upon before mine could be reached. Wearied out with the anxiety of suspense, I consulted one of my senatorial friends. He thought the chance of reaching it to be so small that he advised me to consider it as lost. In a state of mind which I must leave you to imagine, I returned to my lodgings to make preparations for returning home the next day. My funds were reduced to the fraction of a dollar. In the morning, as I was about to sit down to breakfast, the servant announced that a young lady desired to see me in the parlor. It was the daughter of my excellent friend and college classmate, the commissioner of patents, Henry L. Ellsworth. She had called, she said, by her father's permission, and in the exuberance of her own joy, to announce to me the passage of my telegraph bill at midnight, but a moment before the Senate adjourned. This was the turning-point of the telegraph invention in America. As an appropriate acknowledgment of the young lady's sympathy and kindness—a sympathy which only a woman can feel and express—I promised that the first dispatch by the first line of telegraph from Washington to Baltimore should be indited by her; to which she replied: 'Remember, now, I shall hold you to your word.' About a year from that time the line was completed, and, everything being prepared, I apprised my young friend of the fact. A note from her inclosed this dispatch: 'What hath God wrought?' These were the first words that passed on the first completed line in America." The first telegraph-line in America was put into operation in the spring of 1844 at the beginning of Polk's administration. I remember as a boy having the two cities, Baltimore and Washington, pointed out to me on the map, and how the story of the telegraph impressed me. Congress appropriated $30,000 for the construction of the line, and $8000 to keep it running the first year. It was placed under the control of the postmaster-general, and the line was thrown open to the public. The tariff was fixed at one cent for every four words. It was open for business on April 1, 1844, and for the first few days the revenue was exceedingly small. On the morning of the first day a gentleman came in and wanted to "see it work." The operator told him that he would be glad to show it at the regular tariff of one cent for four words. The gentleman grew angry and said that he was influential with the administration, and that if he did not show him the working free of charge he would see to it that he lost his job. His bluff did not succeed. The operator referred him to the postmaster-general, and thus the stormy interview ended. No patrons came in for the next three days, but a great number stood around hoping to see the instrument start up, but no one was willing to invest a cent—probably from fear of being laughed at. On the fourth day the same gentleman who had threatened the young man with dismissal came back and invested a cent, and this was the first and only revenue for four days. The message that was sent only came to one-half cent, but as the operator could not make change the stranger laid down the cent and departed. His name ought to be known to fame as the first man patron of the telegraph. The operation of the Morse telegraph is very simple if we grant all that has gone before. All that is needed is the wire, the battery, and the key, as shown in Fig. 2 (page 99), and a relay—an extra electromagnet which receives the electric current and by its means puts into or out of action a small local battery on a short circuit in which is placed the receiving or recording apparatus. Thus we have a wire starting from the earth in New York and passing through a battery, a key and a relay, and thence to Boston on poles, with insulators on which the wire is strung, and through another instrument, key and battery in Boston, the same as at the New York end, and into the ground, leaving the earth to complete one-half of the circuit. When the keys at both ends are closed the batteries are active and the armatures or "keepers" are attracted so that the armature levers rest on the forward stops. (See diagram Fig. 2.) If either one of the keys is opened the current stops flowing and the magnetism vanishes from all the electromagnets on the line, and a spring or retractile of some kind pulls the armatures away from the magnets and the levers rest on their back stops. In this way all the levers of all the magnets are made to follow the motions of any key. If there are more than two magnets in circuit (and there may be twenty or more) they all respond in unison to the working of one key, so that when any one station is sending a dispatch all the other stations get it. <div class="figcenter"> <big>Fig. 2.</big> <ANTIMG src="images/fig2.jpg" width-obs="100%" alt="Fig. 2." title="Fig. 2." /> A gives a diagram view of a Morse telegraph-line with three stations. B is the battery; C C C, the transmitting keys in the three offices; D D D, the relay magnets; E E E, the armatures that are actuated by the magnets. </div> But there is a "call" for each office, so that the operator only heeds the instrument when he hears his own call. Operators become so expert in reading by sound that they may lie down and sleep in the room, and, although the instrument is rattling away all the time, he does not hear it till his own call is made, when he immediately awakes. In the old days messages were received on slips of paper by the Morse register by means of dots and dashes. Gradually the operator learned to read by sound, till now this mode of receiving is almost universal the world over. Reading by sound was of American origin. It is a spoken language, and when one becomes accustomed to it it is like any other language. This code language has some advantages over articulate speech, as well as many disadvantages. A gentleman who was connected with a Louisville telegraph office told me that one of the best operators he ever knew was as deaf as a post. He would receive the message by holding his knee against the leg of the table upon which the sounder was mounted, and through the sense of feeling receive the long and short vibrations of the table, and by this means read as well or better than through the ear, because he was not distracted by other sounds. A story is told of the late General Stager that at one time he was on a train that was wrecked at some distance from any station. He climbed a telegraph pole, cut the wire and by alternately joining and separating the ends sent a message, detailing the story of the wreck, to headquarters, and asked for assistance. He then held the two ends of the wire on each side of his tongue and tasted out the reply—that help was coming. Any one who has ever tasted a current knows that it is very pronounced. A story similar to this is told of the early days when the Bain chemical system was used between Washington City and some other point. This system made marks on chemically-prepared paper; as the current passed through it left marks on the paper from the decomposition of the chemicals. Some of the preparations emitted an odor during the time that the current passed. The occurrence to which we refer took place at presidential election time. At some station out of Washington an operator was employed who had a blind sister, and this sister knew the Morse alphabet well before she became blind. One evening a signal came to get ready for a message containing the returns from the election. In the hurry, and just as the message had started, the lamp was upset and they were in total darkness—at least, the brother was. The sister, poor girl, had been in darkness a long time. The blind sister leaned over the stylus through which the current flowed to the paper and smelled out as well as spelled out the message, and repeated it to her astonished brother. By the old semaphore system the motions were sensed through the eye as well as the early method of cable signaling. It will be seen from the above that the Morse code may be communicated through any one of the five senses. <hr style="width: 65%;" /> <div style="break-after:column;"></div>

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