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have once chained your current well enough, by an inevitable law it generates another. One of the greatest discoveries of Faraday-that most patient, imaginative, and self-denying of investigators-was that, if a current of electricity passes from a battery along one wire, it developes a current along another and passive wire stretched near it. When Faraday's wonderful discovery of the generation of a current of electricity in a passive wire stretched near a charged one had led to the discovery of relays, new possibilities for telegraphy seemed to be opened on all sides; and these do not seem even yet to have been practically realized even remotely. But to enable the reader to realize even faintly the high point at which telegraphy has now reached, we must take a hurried glance at the development of the system from the beginning. The assertion is certainly fully justified, that the first great step in practical telegraphy was made when the true function of a wire in maintaining a current and producing a signal at the end was clearly grasped. Oddly enough, the first realization of this seems to have fallen to a Scotchman. In the Scot's Magazine for 1753 we find record of an

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expeditious method of conveying intelligence" described under the initials, C. M. There is some doubt now as to who this C. M. was. Sir David Brewster says that he was a Greenock man named Charles Morrison; others give his name as Charles Marshall. Be that as it may, C. M. had caught a vision of the great goal. He aimed at the complete insulation of the conducting wire and producing a signal at the end of the wire which should be visible and intelligible. He did not attain to the next step of producing many signals by one wire; he used a separate wire for each letter of the alphabet. But the principle in his case was clear-he telegraphed. The little that is known of him may be given in the words of an elderly Scotch lady, who remembered a "very clever man of obscure position who could make lichtnin' write and speak, and who could licht a room wi' coalreek." It was a considerable time before the idea clearly dawned on electricians that one wire and needle could be made to represent several letters of

the alphabet. When, by slow degrees, the wires and needles had been reduced to the lucky number five, we may say that a great step in the needle-form of telegraphy had been inaugurated. It was by means of one of these five-needle instruments that the capture of the notorious Tawell, the Quaker murderer, was effected, and a quaint incident is told in connection with it which fixes it the more firmly in the memory. In spite of its five needles the instrument could not make the letter "q," and but for the ingenuity of the telegraphist, who spelt the word "Quaker," "Kwaker," the murderer would in all probability have escaped. But five-needle instruments, useful as they proved in those days, are now looked upon by practical telegraphists as odd specimens of antiquity.

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It took nearly a whole century from the date of C. M.'s somewhat rude invention to make the next fruitful and definite step. Then it was that Messrs. Cooke and Wheatstone introduced what is known as the "double needle" telegraph. On the night of June 25, 1837, it was subjected to trial by wires stretched from Euston Square to Camden Town. At the one end stood Mr. Cooke, at the other Professor Wheatstone. Never," says one of the inventors, never did I feel such a tumultuous sensation before as when, all alone in the still room, I heard the needles click; and as I spelled the words, I felt all the magnitude of the invention, now proved to be practical beyond all cavil or dispute. The double-needle telegraph held its own with considerable distinction for many years, and even now at many of the smaller post-offices, and on most railways, its "lineal descendant" is to be found in the handy "single-needle" instrument, which is electrically and mechanically just a double-needle cut in two.

The next great step in telegraphy was due to America, which, in these later years, has practically monopolized the inventive faculty in this department of science. The name of Morse has become so associated with his form of instrument, that the one is lost in the other. The principle was electro-magnetic. What may be called the "keep

er" of the magnet is an armature or horizontal lever carrying a piece of pointed metal or "style," which embosses a mark upon a band of paper carried forward by wheel-work. The system of dots and dashes identified with the name of Morse, or a mere modification of its working, is that now generally in use throughout the world. If Morse, who had abandoned a promising career as an artist for the love of electrical experiment, did not realize the last possibility of his own ingenious invention, he may be said to have laid down the principles of all further development. It has been well said:

The great defect in the original " Morse" instrument, or, as it is commonly called, the "embosser," is the difficulty of reading, unless under certain conditions of light and shade, the embossed marks on the strip of paper, as well as the unpermanent character of the record. This may, however, be said to have been a mere difficulty of detail, overcome by the introduction of the ink-writer-in connec tion with which it is proper to mention the name of Messrs. Siemens, of London and Ber

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lin. The manipulation and electrical action of this instrument are in all respects the same as those of the "Morse," in fact it is, to all in tents and purposes, a Morse," with the important addition of the ink-writing principle. The lever attached to the armature, which, in the "embosser," holds a style for the indenta tion of the strip of paper, has, in the case of the ink-writer, a small disk attached to it. This disc rests in a well or trough filled with specially prepared telegraphic ink, and each time the armature is drawn toward the electromagnet, the disk is raised by means of the lever arrangement, and being thus brought into contact with the paper as it is unwound from the instrument, resembling the manner in which the paper is unwound in the new" Walter" printing machine, beautifully distinct marks or signs are made, in place of the somewhat faint indentations produced by the original instrument. These ink-writing instruments are of two kinds, telegraphically described as double and single current ink-writers; the former being used for long distances, where the signalling is more labored and difficult, and the latter for short distances, and generally throughout the metropolis.

The name of Wheatstone soon recurs in the annals of telegraphic invention in connection with his automatic system, of which the distinguishing feature is that the messages are prepared beforehand by being punched out on a strip of paper, somewhat after the manner of the pattern of a Jacquard loom. This done, the slip is simply passed through a machine called the transmitter" or

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'sender," by means of turning a handle for the purpose, when, owing to the electric current being broken or maintained, according to the different perforations in the paper, the message is recorded at the distant station in exactly the same form as by the ordinary Morse instrument. The transmitting process (that is, after the preliminary punching has been accomplished) is of so entirely mechanical a nature, that steam or other power might be applied to the working of the machine, and messages may be sent ad infinitum at a speed something like four times as great as that attained under the hand" system.

Of all the modern inventions in telegraphy, this is at once the most wonderful, the most interesting, and the most useful. By its means the capacity or carrying power of a wire can be increased fourfold, with of course a corresponding increase of staff at both ends; it is tolerably certain that the Post Office could not have coped with the immense increase of traffic which has taken place since its acquisition of the telegraphs, but for the largely extended use which is now made of this description of apparatus, pending the erection of new wires. This invention was only in what might be termed its experimental stage when the Post Office took over the telegraphs-not more than two or three sets of apparatus of this kind being in use by all the companies put together. Now, however, there are some scores at work in the great Central Telegraph Office, and every provincial town of any importance has one or more of these fast-speed appliances.

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And Morse, although the principle of his original instrument has been improved upon and adapted, still contrives to maintain his prestige and to perpetuate his fame, by what is called the Morse sounder," which has been designated the "telephone of symbolic telegraphy;" being at once cheaper to make, to work, and to maintain than the printing-machine of the early days of Post Office telegraphy. And speaking of sound telegraphs recalls the "Bell" instrument of Sir Charles Bright, which may be said to have accompanied the double-needle instrument into honorable retirement. In this interesting form of telegraph two bells of different pitch

were fixed on a frame sufficiently apart to admit the head of the operator, who, with a bell close up to each ear, interpreted the sounds as they were given out with almost lightning rapidity.

The Morse sounder is practically the Morse instrument. But inasmuch as the principal part of a recording instrument is that connected with the unwinding and marking the paper, the sounder may be said to be the mere skele

ton of the printer. The clock-work is altogether dispensed with, and the apparatus may be said to resolve itself into a pair of coils, and an armature, the stroke of which, as it is attracted by the electric current, creates the sound from which the signals are interpreted. In fact, it is little more than an electro-magnet, which may almost be carried in the waistcoat pocket, while the Morse recorder, or printer, can hardly be accommodated in a smaller space than eighteen inches square. Difference of sound in the bell instrument has been substituted by duration of sound in the Morse sounder; and just as a stroke on the left-hand bell indicated the dot" of the Morse alphabet, or the letter "E," so a momentary click of the armature is similarly interpreted on the sounder, while a more decided click would represent the dash" of the Morse alphabet, or the letter "T."

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The Post Office erred on the side of caution in regard to duplicate, adopting the view so strongly held by the leading telegraph companies that some kind of record or other was necessary to the accurate transmission and decipherment of the messages. But lately experience has told in favor of "sound reading."

Another interesting and ingenious form of telegraphy is to be seen in the "Hughes" type-printing instrument, which delivers its message in bold Roman characters, and which, although discarded by the Post Office, is extensively used by the Submarine Telegraph Company, and on the Continent.

It would be entirely beyond our scope to enter into any elaborate account of the telegraph galleries at the central office in London. Here we see most of the more recent instruments in active work. "Direct writers," which can deliver with ease forty messages an hour, duplex and quadruplex instruments, and single needles for shorter distances. The rapidity with which the ribbon-like bands of printed messages which faithfully preserve record are thrown out is truly astonishing. While we listen to the hurried click-click which would to a stranger soon become altogether confusing, our attention is directed to some

"sound" instruments, which demand. the greatest nicety and tact in their treatment.

Here, too, we see all round the sides of the great gallery the receiving and despatching boxes of the pneumatic tube system, through which, as we have seen, messages are blown with the speed of lightning. What would perhaps prove as interesting to the general visitor, who cannot profess to grasp all the details about electrical systems, currents, needles, and insulators, is the composite character of the staff here, and the air of energy, industry, and enthusiasm which everywhere prevails. Great prominence is given to female labor. There are over 700 female clerks in this department of the public service, and, judging from appearances, they could hardly be more happily employed. The whole world," said Mr. Scudamore, is the country of the telegraphist. Sitting at one end of a wire, no matter what its length, he converses as easily with the clerk at the other end as if he were in the same room with him. Strange as it may seem, he knows by the way in which the clerk at the other end of the wire does his work, whether he is passionate or sulky, cheerful or dull, sanguine or phlegmatic, ill-natured or good-natured. He soon forms an acquaintance with him, chats with him. in the intervals of work, and becomes as much his companion as if he were working face to face with him."

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And there is a story told by Mr. Scudamore of a clerk in London who formed an attachment for, and finally married, a clerk in Berlin with whom he worked; a relation which, we understand, has since then been repeated with varying attendant circumstances.

It is indeed not a little surprising to find that electricity, under some circumstances, may be superseded by air. To create a vacuum in a pipe or tube is merely a mechanical process, accomplished in an instant by a powerful steam engine; and for short distances, especially within great cities, it has been found a greater saving of time to use such tubes for the despatch of the actual written message than to re-telegraph them from a general centre. matic tubes in London extend to some twenty-one miles; and the following

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very admirable description of the system has been written by one who has given much study to the subject:

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Twenty miles of pneumatic tubes are terminated in graceful curves at what is called the "tube-board," which runs along the entire length of the central gallery, and at each of the thirty tubes thus represented is stationed a smart boy-attendant. Each tube is fitted with an elaborate and costly brass apparatus for regulating the pressure and vacuum to be applied to it, and with an electric bell for signaling purposes. The carrier," in which the messages are inclosed for transmission, is a round tube-like box made of gutta percha, and covered with several coatings of felt, so as to make it nicely fit the pipe through which it has to travel. The messages are rolled up tightly and placed inside the carrier, either singly or in half-dozens, as the pressure of business requires. The carrier is inserted in the mouth of the tube, pressure is turned on by the attendant, and away it goes, round the curve which takes it up nearly to the roof of the gallery, down through the flooring to the level of Newgate Street, until, speeding its way along busy thoroughfare and quiet court or alley, it reaches its point of destination, where it will probably ascend to the top of the building in which the office is situated, apparently for no other purpose than to descend again into the basement and project itself under the very nose of the messenger boy whose duty it is to "uncork" the messages and run with them to their final destination. The operation takes longer to describe tnan most carriers occupy in travelling from St. Martin's-le-Grand to their destination; and we need scarcely point out that by simply reversing the process-i.e., by exhausting instead of charging the tubes-carriers are drawn or sucked inward, as easily and quickly as they are blown or puffed outward.

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It is somewhat surprising to learn that practical telegraphists realize more and more that the increase of cheap telegraphy between various parts of London is more likely to lie in the extension of the tubes than otherwise. Pneumatic telegrams' which could be sent closed as a letter and delivered as they are received would certainly be found of great value, lending themselves to a large class of correspondents who do not care to commit their secrets to telegraph clerks, however skilfully contracted and disguised or transferred to imperfect cipher. So long ago as the sitting of the Commission on Telegraphs in 1876, we find that this topic was made prominent. Mr. R. W. Johnston, on being asked the question: "Have you at all considered any form by which telegrams might be sent to the public without any loss of facilities, and in a NEW SERIES.-VOL. XXXIV., No. 6

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cheaper mode to the Post Office?" answered:

I have been considering that in London, at all events, for the purpose of a cheap local telegraph rate, the pneumatic system might be largely extended; my impression is now, and has been for some time, that London will never be properly served, telegraphically, until the pneumatic system is very considerably extended. I think that at Charing Cross, for example, to which point we have two large tubes of considerable capacity now going, we ought to have a sub-central pneumatic station, with tubes laid to the House of Commons, which would also include an important office in Parliament Street, and likewise that in Westminster Hall, and also to Piccadilly, which would include an important office in Piccadilly Circus, and probably also 'an office in Regent Street; and by these means I think that cheap local telegraphy might be secured. The cost, no doubt, would be considerable at first, but the advantage as regards a system of communication of this kind is, that the cost of laying down, at all events, is final, because there is practically no limit to the "life" of a pneumatic tube, and we know that underground wires deteriorate almost as much as over-house wires.

Is it not likely that a large expenditure may have to be incurred in the metropolis in putting down underground wires instead of overhouse wires ?—I do not know that the expenditure in the area which I contemplate for the pneumatic tube system would be as great as the expense in other parts of London, but no doubt it would be considerable.

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And again, in answer to the following question : 'Do you mean this pneumatic tube to be applied simply for sending telegraphic forms, or for sending pneumatic letters also ?" he said:

I can readily conceive of a system whereby a telegram can be written-say in an office in the city and put in an envelope instead of writing the name of the addressee inside the message, and the envelope would be stamped with the proper payment of the telegram, and sent through the tube and delivered, without any clerical expense whatever.

Further question:

By that system of pneumatic letters, would you not save a great amount of clerical labor and clerical charges?—Yes; a very great deal.

And might not the expenditure upon those tubes, although the capital might be considerable, be repaid by saving the cost of clerks and other persons?—I should say so.

Have you been considering, also, the question of sending a less amount of words in ordinary telegrams throughout the country ?-I have been considering, as a corollary of the proposal made by me in a report which, I think, has been printed and laid before the Committee, that we should abandon the system

of getting the sender's address in the form as an address, and adopt the practice which prevails upon the Continent, and also, as it would

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appear from Colonel Robinson's evidence, in India, and simply require the signature; if we have the address, let it be put upon the form as a mere record, and not for any purpose of signalling.

But, supposing the sender desires his address to be sent, do you not think that a little extra payment might be made so that the address might be sent ?-Yes; I think so.

Will you hand in that form you suggest?— I will.

According to this form, the signature of the sender is at the end, and the space between is divided into two parts; the address upon the left, if it is not to be telegraphed, is not paid for; whereas, if the sender wishes his address to be telegraphed, it is placed upon the right-hand side?—Yes; it is placed upon the right-hand side, and if the sender wishes it to be sent it must be paid for.

Do you think that form would practically give to the public all the facilities which they now possess and be a great gain to the Post Office?—Yes; I do. I am quite satisfied that our present system encourages the senders of many telegrams to run to waste with regard to their addresses.

When you speak of the direct advantage likely to arise from the adoption of that plan, are you referring to a direct increase of revenue or in the way of liberating the wires? Not so much in direct revenue as in liberating the wires; there would be some direct revenue of course.

The pneumatic system has been for some years in use in Manchester and Birmingham, and was recently extended to other four of the principal English towns; and has now a length of tube at its command exactly ten times greater than what existed ten years ago. Lon

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would appear that the pneumatic letter system. "blow-post," as it is characteristically termed, is in operation in Berlin at this moment, and is in course of being considerably extended. The system, when complete, will comprise twenty-six kilometres of tubing and fifteen stations. The tubes will be of wrought iron, having a bore of sixty-five millimetres, and they will lie about one metre below the surface of the ground. Wrought-iron tubes are the exception in our pneumatic system, the method generally adopted being a leaden tube inclosed in a cast-iron pipe. We are, of course, unable to pronounce upon the merits of the two systems, although it would appear, on the face of the matter, that the freedom from corrosion, and the smoother surface afforded by such a workable metal as lead, are all in favor of an easier and more rapid working. The exhausting machines and apparatus required for working the Berlin system are situated at four of the fifteen stations. Both compressed and rarefied air, or a combination of the two, are employed in propelling the carriers," or boxes, into which the telegrams, or letters, are placed, and steam-engines of about twelve-horse power are used in condensing and rarefying the air. Each of the four main stations has two engines, which drive a compressing and an exhausting apparatus, and large containers, or reservoirs, are used for the condensed and rarefied air. The tension of the condensed air is about three atmospheres, and that of the rarefied about thirty-five millimetres of mercury; and the former, heated to 45 degrees C. by the act of compression, is cooled in the reservoirs, which are surrounded with water. The letters and cards which have to be forwarded are of a prescribed size, twenty being the complement assigned to each 'carrier." From ten to fifteen carriers are packed and forwarded at a time-a sort of pneumatic "train," in fact; and behind the last vehicle' is placed a box with a leather

don alone, as we have seen, has upward ruffle, in order to secure the best closure of the

of 37,000 yards, or more than twentyone miles, of leaden pipes buried beneath its streets, through which open telegrams are being sucked at all hours of the day and night, which seems astonishing; and yet practical men say that the system should in London be very largely extended.

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Other countries have availed themselves of the golden opportunities which the evidence given before our Commission suggested; and we regret that, as regards pneumatic letters" (télégramme fermée), we in England are precisely in the same position as before. We read as follows in a recent article on the subject, and we may well be sorry at the losses and failures on our own part which it points out :

Whether the German Post Office officials have been studying a report intended for our own postal authorities we do not know, but it

tube. The velocity of the carriers averages 1000 metres per minute, and a train is despatched every quarter of an hour, each of the two circuits or routes into which the system is divided being traversed in twenty minutes, including stoppages. The entire cost of this novel and apparently complete system is estimated at 1,250,000 marks; and it is always well to remember, in speaking of the cost of a pneumatic system, as compared with that of an ordinary telegraph, that the outlay is as nearly final as possible, there being practically no limit to the "life" of a pneumatic tube, especially if it be constructed of lead and protected from external injury by an outer coating of 3d. in Berlin, or about one-fourth of the cost blow-post' letter appears to cost

iron. A

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of a telegram, and the average time of delivery in any quarter of the city is stated to be one hour. Admitting our own Metropolitan tele

graphic system to be perfect as far as it goes, it is perfectly clear, from the report of the Select Committee already referred to, that a cheaper rate that Is. for local telegrams is not to be hoped for so long as the costly machinery of wires, instruments, and clerks, is maintained

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