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From the date of the discovery that electricity could be conducted to a distance, dreams were indulged that it could be made a means of communicating intelligence. In the eighteenth century, many attempts were made to carry intelligent signals over electric wires. Some of these were quite ingenious, but in the end failures, because the old-fashioned frictional electricity was the only kind then known and employed. Even after the discovery of the voltaic cell or battery, which afforded an ample supply of chemical electricity to operate a telegraphic apparatus, the time was not ripe for successful telegraphy, for up till 1830 no battery had been produced that was sufficiently constant in its operation to supply the kind of current required. For feasible telegraphy, two important steps were yet necessary. One was the discovery of the electro-magnet, 1825–30. The other was the discovery of the Daniell’s battery or cell, in 1836, by means of which a constant electric current could be sustained for a long time.

DANIELL’S CELLS.

But even before these two indispensable requisites had been supplied by human genius, much had been done to develop the mechanical methods of conveying intelligence. In 1816, Ronalds, of England, constructed a telegraph by means of which he operated a system of pith-ball signals which could be understood. In 1820, Ampère suggested that the deflection of the magnetic needle by an electric current might be turned to account in imparting intelligence at a distance. In 1828, Dyar, of New York, perfected a telegraph by means of which he made tracings and spaces upon a piece of moving litmus paper, which tracings and spaces could be intelligently interpreted through a prearranged code. A little later, 1830, Baron Schilling constructed a telegraph which imparted motion to a set of needles at either end.

MORSE TELEGRAPH AND BATTERY.

From this time up to 1837, which last year was a memorable one in the history of telegraphy, the genius of such distinguished men as Morse in America, Wheatstone and Cooke in England, and Steinhill in Munich, was brought to bear on the further evolution of the telegraph. While all these names have been associated with the invention of the first practical telegraph, it is impossible, with justice, to rob that of Morse of the distinguished honor. Morse conceived his invention on board the ship Surry, while on a voyage from Havre to New York, in October, 1832. It consisted, as conceived, of a single circuit of conductors fed by some generator of electricity. He devised a system of signs, which was afterwards improved into the Morse alphabet, consisting of dots or points, and spaces, to represent numerals. These were impressed upon a strip of ribbon or paper by a lever which held at one end a pen or pencil. The paper or ribbon was made to move along under the pencil or pen at a regular rate by means of clockwork. In accordance with these conceptions, Morse completed his instrument and publicly exhibited it in 1835. He gave it further publicity, in much improved form, in 1837. In this form it was entirely original in the important respects that the ribbon or paper was made to move by clockwork, while a pen or pencil gave the impressions, thus preserving a permanent record of the message conveyed.

SAMUEL FINLEY BREESE MORSE.

Though under systems less original and effective than that of Morse, a first actual telegraph had been operated between Paddington and Drayton, England, a distance of 13 miles, in 1839, and one at Calcutta, India, for a distance of 21 miles, it was not until 1844 that the world’s era of practical telegraphy actually set in under the Morse system, which speedily superseded all others. In that year, amid the jeers of congressmen and the adverse predictions of the press, Morse erected the first American telegraph line in America, between Baltimore and Washington, a distance of 40 miles, and, to the confusion of all detractors, sent the first message over it on May 27 of that year. From that date the fame of Morse was established at home, and soon became world-wide. His system of telegraphy, with slight modifications, became that of all civilized countries.

CYRUS W. FIELD.

As was to be expected in a century so full of enterprise as the nineteenth, a science so attractive, so useful to civilization, so commercially valuable, so full of possibilities, as telegraphy, could not remain at rest. Everywhere it stimulated to improvement and new invention and discovery; and as the century progressed, it witnessed in steady succession the wonders of what became known as duplex telegraphy, that is, the sending of different messages over the same wire at the same time. Again, the century witnessed the invention of quadruplex telegraphy, that is, the sending of four separate messages over the same wire, two in one direction and two in another. This was followed by the invention of Gray’s harmonic system, by means of which a number of messages greater than four are transmitted at the same time over the same wire; and this again by Delaney’s synchronous multiplex system, by means of which as many as 72 separate messages have been sent over the same wire at the same time, either all in one direction, or some in one direction and the rest in an opposite.

For a time successful telegraphy was limited to overland spaces, the conductors or wires, consisting of iron or copper, being insulated where they passed the supporting poles. In the cities, supporting poles proved to be unsightly and dangerous, and they were succeeded by underground conduits carrying insulated wires. In 1839, we read of what may be reckoned the first successful experiment in telegraphing under water by means of an insulated wire, or cable, as a conductor. The experiment was tried at Calcutta, and under the river Hugli. In 1842, Morse experimented at New York with an under-water cable, and showed that a successful submarine telegraphy was practical. In 1848, a cable, insulated with gutta-percha, was laid under water between New York and Jersey City, and successfully operated. In 1851, a submarine cable was laid and successfully operated under the English Channel. An enterprising American, Cyrus W. Field, of New York, now took up the subject of submarine telegraphy, and suggested a cable under the ocean between Ireland and Newfoundland. One was laid in 1857, but it unfortunately parted at a distance of three hundred miles from land. A second was laid under Mr. Field’s auspices in 1858, but the insulation proved faulty, and after working imperfectly for a month, it gave out entirely.

OCEAN CABLE.

These disasters, though furnishing much valuable experience, checked the enterprise of submarine telegraphy for a number of years. Not until 1861, when a deep-sea cable was successfully laid and operated between Malta and Alexandria, and in 1864, when one was laid across the Persian Gulf, did enterprise gain sufficient courage to dare another attempt to cable the Atlantic. In 1865, that attempt was made. Again the cable broke, but this did not dissuade from another and successful attempt in 1866. This signal triumph was the forerunner of others, equally important to international commerce and the world’s diplomacy. Countries far apart, and isolated by oceans, have, by means of deep-sea cables, been brought into intimate relation, and made sharers of one another’s intelligence, enterprise, and civilizing instincts. What the overland telegraph has done toward bringing local states and communities into contact, the submarine cable has done for the remote nations.

In form, an ocean cable differs much from the simple wire which constitutes the conductor of an overland or even underground telegraph. It is made in many ways, but mostly with a central core of numerous copper wires, which are more flexible than a single wire. These are thickly covered with an insulating material, such as gutta-percha, after first being heavily wrapped in tarred canvas or like material. The central cores may be one, two, three, or even more in number. Where a cable is likely to be subjected to the abrasion of ship-bottoms, rocks, or anchors, it has an outer covering or guard composed of closely united steel wires. In submarine telegraphy, the instruments used in sending and receiving the message are very much more ingenious, delicate, and costly than in overland telegraphy.

Whereas at the beginning of the nineteenth century electric telegraphy was an unknown science, and even up to the middle of the century was of limited use and doubtful commercial value, nevertheless the end of the century witnesses in its growth and application one of its most stupendous marvels. From the few miles of overland wires in 1844, the total mileage of the century has expanded to approximately 5,000,000, and the submarine to 170,000. A single company (the Western Union) in the United States operates 800,000 miles of wire, conveying 60,000,000 messages per year, while throughout the world more than 200,000,000 messages per year serve the purposes of enlightened intercourse. The capital employed reaches many hundreds of millions of dollars.

The close of the nineteenth century opened possibilities in telegraphy that may be classed as startling in comparison with its previous attainments. It would seem that the intervention of the familiar conducting wire is not absolutely necessary to the transmission of intelligence. The old and well-established principle of induced currents has lately been turned to account in what is termed “telegraphy without wires.” As an instance, a telegraph wire, when placed close alongside of a railroad track, will take up and convey to and from the stations the induced pulsations of a magneto-telephone placed within a passing car, and connected to the metallic roof of the car. This system has been put to practical use on at least one railway, and pronounced feasible.

But a greater marvel than this springs from the discovery of Hertz, about 1890, that every electrical discharge is the centre of oscillations radiating indefinitely through space. The phenomenon is likened to the dropping of a stone in a placid lake. Concentric undulations of the water are set up,—little waves,—which gradually enlarge in diameter, and affect in greater or less degree the entire surface. Could an apparatus be invented to detect and direct the oscillations made in space by an electric generator,—to perceive, as it were, the ether undulations, just as the eye notes those on the lake’s surface?

In 1891, Professor Branley found that the electric vibrations in ether could be detected by means of fine metallic filings. No matter how good a conductor of electricity the metal in mass might be, when reduced to fine filings or powder it offered powerful resistance to a passing current; in other words, became a very poor conductor. An electric discharge or spark near the filings greatly decreased their resistance. If the filings were jarred, their original resistance was restored. Branley placed his filings in a tube, into either end of which wires were passed. These were connected with a galvanometer. Ordinarily, the resistance of the filings was such as to prevent a current passing through them, and the galvanometer remained unaffected. But when an electric spark was emitted near the tube, the resistance was so much decreased that the current passed readily through the filings, and was detected by the galvanometer. This is simply equivalent to saying that the discharge of the electric spark made the filings to cohere and become a better conductor than when lying loosely in the tube. Here, then, was opportunity for an instrument which had but to regulate the number of sparks and indicate the presence of the electric waves in order to produce dots and dashes similar to those used in the common telegraph. Such an instrument was brought nearest to perfection by Signor Marconi, a young Italian, in 1896. With it he succeeded in sending electric waves through ether or space, and without the use of wires, a distance of four miles, upon Salisbury Plain, England. Later, he transmitted messages by means of space (wireless) telegraphy across Bristol Channel, a distance of 8.7 miles, and subsequently across the English Channel, a distance of 18 miles. Mr. W.J. Clarke, of America, has improved upon Marconi’s methods of space telegraphy, and shown some remarkable results. Whether space telegraphy will eventually supersede that by wires is one of the problems that time only can solve. But such are the possibilities of electrical science that we may well be prepared for more wonderful revelations than any yet made.

THE GREAT EASTERN LAYING AN OCEAN CABLE.