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electric force to accomplish its work may Britain. Some of these will be noticed further be transmitted through the wire for long dis- on.-An electric copying telegraph was inventtances (as has occurred between New Yorked by Mr. F. O. Bakewell of England in 1850, and Boston), with the wire actually lying upon designed for giving an exact copy of the mesthe ground during a heavy rain storm. So little sage sent. This is written with a pen dipped power is required to work it under ordinary cir- in varnish upon a sheet of tin foil, which is cumstances, that 10 cups of the Grove battery then laid around a metallic cylinder, correhave been found sufficient between Boston and sponding precisely in its size, rate of revolution, New York. This telegraph, like most of the and longitudinal movement, with another cylothers excepting the Morse, requires an alarum inder at the receiving station, which is covered bell to call the attention of the operator when with chemically prepared paper and provided a message is to be sent from another station, with an index like that of the Bain chemical and for this an electro-magnet is employed dis- telegraph. These cylinders being set in motinct from the registering apparatus. Mr. Bain tion at the same instant, the index of the regismade many other inventions in the telegraph, tering apparatus makes a continuous colored several of which are too remarkable to be line, running round the cylinder in a close spipassed over. One of these, adapted for trans- ral so long as the metal style at the other stamitting words at the extraordinary rate of tion presses upon the tin foil; but as this passes 5,000 per hour, employed at the sending station over the lines of varnish a break in the circuit narrow strips of paper perforated with holes occurs, causing an interruption of the colored and elongated slits, making the message in line at the other station. The blank spaces these regular characters of the system. These thus produced will be found when the lines strips (prepared beforehand) were passed in have been drawn over the whole paper to be a succession over a cylinder of metal with a pin facsimile of those written in varnish upon tho connected with the wire so placed as to press tin foil. The lines, though drawn as spirals lightly upon the paper and enter each hole as upon a cylinder, appear as parallels when the it passed along and complete through it the cir- paper is taken off. About 10 revolutions of cuit. At the other station similar strips of chem- the cylinder, making as many parallel lines, are ically prepared paper were passed at precisely sufficient to complete one line of writing; a the same rate under the same sort of style as cylinder 6 inches in diameter affords sufficient that just described, and colored marks were length for about 100 letters of the alphabet in thus produced exactly corresponding to the one line; and as the rate of revolution is not holes in the paper at the transmitting station. less than 30 in a minute, 300 letters or more The advantage of this system is in the trans- may be transmitted in this period. A mesmission of very long messages which may be sage in cipher can be sent by this method withprepared in separate parts by a number of oper- out risk of error, and even invisible messages ators; or, as is now done, by the use of a very written in colorless varnish may be received ingenious machine which perforates the paper and impressed in invisible characters upon prewith great rapidity, as it is worked by striking pared paper, to be afterward brought out by keys like those of a piano. The difficulty in the chemical means; thus, if the paper be moistpractical application of this telegraph appears to ened with diluted acid alone, no visible mark be the want of some efficient means of exactly is left upon it until it is brushed over with regulating the speed of the apparatus. The uni- a solution of prussiate of potash, when the versal telegraph of Prof. Wheatstone, recently lines appear in their blue color.—The patent introduced in London, is based on this principle. for the House printing telegraph was issued Another of his inventions was a printing tele- by the U. S. patent office in 1848, but bears graph, in which types arranged around the pe- date April 18, 1846, when it was first applied riphery of a wheel were brought successively for. It was with this apparatus that the first opposite the face of a cylinder covered with printed despatch ever produced upon a telepaper and instantly pressed against it, while graph line was sent, in the autumn of 1847, from the cylinder turned at a regulated speed around Cincinnati to Jeffersonville, opposite Louisville,

a its axis, and at the same time was carried lon- Ky., 150 m. The system is regarded as one of gitudinally along it so that the printed lines the most wonderful and complete of the extrapassed in spirals from one end of the cylinder ordinary inventions developed by the telegraph. to the other. The electric current caused the The necessity of avoiding the peculiar features rotation of the wheel having the types, and upon which other telegraphic systems were esalso stopped or liberated the other movements tablished, in order to give to it a distinctive which depended upon springs and clockwork. and patentable character, added greatly to the The machines at the different stations are pre- difficulties of the undertaking, which however cisely alike, and all their movements are per- were after nearly 6 years of labor overcome fectly synchronous. A printing telegraph of by the ingenuity and perseverance of Mr. House. somewhat similar construction was invented in The apparatus is too complicated for any de1837 by Mr. Alfred Vail of New York; and scription of it to be made intelligible without others have been produced by M. Froment in illustrations, and little more can be attempted France, Royal E. House of Vermont, David E. than to state its great powers of execution and Hughes of Kentucky, and Jacob Brett in Great its perfect accuracy. The mechanical movements of this machine are set in action by are of longer duration than those making merehand labor applied to a crank, which works an ly dots. The saving of time thus effected is of air pump for the purpose of supplying a current great importance, especially on long lines in of condensed air, which under the control of which an appreciable amount of time is expended the electric current carries forward the move- in the passage of the current. In long lines of ments of the composing and printing apparatus, submarine telegraphs, as will be noticed below, so that each letter may be printed at the exact a greatly increased resistance is experienced in instant that it is struck upon the key-board of charging the wires with the electric current, the instrumeut. This key-board, which resem- and the impulses necessarily succeed each other bles that of a piano, is connected with the elec- with extreme slowness and diminution of force. tric current, and as the keys are struck the The type wheel in the Hughes system is procircuit is opened and closed with the move- vided with 28 types; it is kept in rapid revoluments of a circuit wheel which controls the tion during the whole time of operating, and is movements of the type wheel. A complete so perfect in its movement, that though the revolution of the circuit wheel, coming round revolutions may be from 100 to 140 per minute, again to the same letter, breaks and closes the the variations of two machines at different stacircuit 28 times, and other letters a less number tions do not exceed or of a second in several according to their arrangement on the type hours' running. At the instant one of the 28 wheel. The printing apparatus is quite distinct keys of the key-board, which is like that of from the circuit, but the composing apparatus the House telegraph, is depressed, the current forms a part of it. The impression of the letter entering the magnet at the distant station causes is produced by a blackened ribbon being press- the strip of paper to be brought against the ed against the paper by the type. From the type opposite to it at the time, and receive the galvanic battery of one station, the current impression in ink while this is rapidly carried passes along the wire to the next station, then round with the wheel. The operator can send through the coil of an axial magnet to the in- an average of two impulses with each revolusulated iron frame of the composing machine, tion of the type wheel, thus making the caand thence to a circuit wheel revolving in this pacity of the instrument full 200 letters or frame. Through a spring that rubs on the 40 words per minute, and the maximum is edge of this wheel it passes into the return much above this. The regulators or governwire, and through another battery back to the ors of the clockwork which carries the type first station to pursue the same course through wheels at the different stations are of an enthe composing machine and magnet there and tirely novel character. These are springs of all others upon the line. In sending a message, the same musical tone, which consequently the operator sets his machine in motion and vibrate the same number of times per second, gives a signal by breaks of the circuit, repeated and which control by their vibrations the eså different number of times for different offices capement of the apparatus. The power of the on the same wire. As this is heard by the electric current required is reduced in a wonoperator at the receiving station, he sets his derful degree by the combination of the natural machine in motion, and the type wheel at its magnet and the electro-magnet, making only so starting point, and signals back that he is much electricity necessary as will neutralize ready. No further attention is required on his the magnetism in the natural magnet by causpart, while the machine goes on, printing in ing magnetism of an opposite polarity to be Roman capitals the communication upon the created in the poles of the electro-magnet. long strip of paper regularly supplied to the This extreme delicacy, however, renders the type wheel. Two hundred and fifty to 260 let, telegraph liable to be interrupted by atmosters as a maximum can be accurately printed pheric electricity, such as is developed previous every minute, and over 3,000 words an hour to and during the continuance of the aurora of press news, partly abbreviated, have been borealis. It is asserted that this instrument sent over the wires with a single instrument.— can work upon a longer line without the aid The inventions of Mr. Hughes, patented May of repeaters than any other, and this with an 20, 1856, showed that the field of discovery in extraordinarily low battery power. In the telegraphing was far from being exhausted, by winter of 1858 a new instrument was perfected introducing apparatus even more wonderful in by G. M. Phelps of Troy, combining the most its operation than any which had yet preceded valuable portions of both the House and Hughes it. His was a printing telegraph, in which the patents, and which has been introduced with feat of printing a letter with every impulse or great success on nearly all the lines formerly wave of the electric current was accomplished. using those inventions. This has appropriately In the other telegraphs, as already described, been termed the "combination" instrument, several impulses produced by successive closings and has the advantage of being able to work or break

the circuit are required to form a through a much longer circuit than the House single letter; this in House's telegraph varies up machine, with a smaller battery, as well as of to 14 breaks, the maximum required for repeat- being much simpler in construction. The keying the same letter, and averages about 7 im- board and transmitting machinery of this inpulses; and in the Morse system the average is strument are precisely like those of Hughes, as about 3} impulses, some of which making lines is also the printing apparatus, with the excep

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tion of the electro-magnet, which is of the ordi- feet above the ground, and placed from 80 to nary form, and operates upon the type wheel 100 yards apart. If made of red cedar or lothrough the medium of compressed air as in cust and about 10 inches diameter at the base, the House machine. The vibrating spring used they may in general be depended upon for 30 by Hughes as a governor is superseded in the or 40 years; but some poles decay in 3 or 4 combination instrument by a most ingenious years. The durability of other woods may be electro-magnetio governor, the invention of increased by thoroughly coating them with Mr. Phelps. It consists of a hollow iron drum, coal tar. In Europe it is common to saturate geared to the transmitting cylinder and type the wood with some of the chemical preparawheel of the instrument and moving with them, tions noticed in PRESERVATION OF Wood. In but much faster. If the machinery has a ten- crossing rivers, where, on account of the swiftdency to revolve too rapidly, the increased cen- ness of the current or the danger of disturbance trifugal force, acting upon a detached section from drift wood, ice, or the anchors of vessels, of the drum, actuates a series of levers inside, an insulated wire could not safely rest upon by which a spring is raised, closing the circuit the bottom, masts are erected on the opposite of a local battery through an electro-magnet. shores, sufficiently high for the wire suspended A friction brake, which is applied to the re- between them to be above the reach of the masts volving drum by the attraction of this magnet, of boats and vessels that navigate the stream. instantly reduces the speed to the required The longest span in Europe is one of 1,700 feet limits, when the local circuit is again broken. over the Niemen river at Kovno, in Lithuania. The combination is considered to be the most In the United States there are many much perfect printing instrument yet produced.- longer crossings. That formerly used over the Among the several telegraphs employed in Eng- Hudson river at Fort Lee was of 2,700 feet; land, those of the “Magnetic Telegraph Com- but the river is now crossed from the foot of pany" are worked by magneto-electricity, thus 14th street to Hoboken by 6 sunken cables, each dispensing with voltaic batteries, the use of having 3 conductors. The Mississippi is crossed which involves much care and expense. The at St. Louis in two spans, one of 2,700 and one apparatus is remarkably compact, without clock- of 2,200 feet; and near Cape Girardeau, 2,980 work or complicated movements such as are feet, from a mast on the Ilinois shore 210 feet common in other telegraphs. Though used dou- high to one on the Missouri shore 205 feet high, ble with two sets of magnets, with a wire from from a base 110 feet above the water. The each connecting with two needles upon the dial Ohio at Paducah is crossed in two spans, one at the opposite station, the whole apparatus of 2,400 and one of 3,720 feet. At the last including the tablet or dial occupies but a few named point, on the Kentucky side, the mast is inches space, and is always ready for instant 307 feet high above a bank 32 feet from the wause, however long it may have remained inac- ter; on the island in the river is a mast 205 tive. The magnets, of horse-shoe form, about feet high, and on the Illinois shore is one 215 12 in number for each set, are about 15 inches feet high. Such masts require strong bracing long and 1} broad. They are laid one upon to bear the strain of the wire with so long a another in two piles near together, and fastened leverage, and resist the action of the winds. down to the table by screws. Opposite the The wire employed in these crossings is of iron ends of each pile, placed upon a rotating axis, known as No. 16, and weighs about 63 lbs. to is the soft iron armature, consisting of two cyl- the mile. Sunken cables are fast taking the inders wound around with long coils of fine place of all such river crossings. The ordicopper wire covered with cotton. The wire nary telegraph poles require to be of sufficient of the two coils is connected together, and one strength to sustain a weight of over 400 lbs. end of each passes in a spiral through the axle suspended upon the wire between them, and to the platform upon which the apparatus rests. at corners they should be still stronger. The One end is thence carried into the earth, and following table represents the common numthe other goes to the electro-magnet of its bers of iron wire used for this purpose and its own dial, thence to the distant station, and strength, as plain wire, and also when coated through the instrument there into the earth. with zinc, the figures representing in pounds The same arrangement is repeated with the the strain at which each kind broke. The other set. The axis of each armature extends American wire is stronger than the English, and toward the operator, and is provided with a about equal in this respect to the Swedish : crank handle by which each is turned to generate the electric current. The effect is seen in the movement of the two needles placed upon

2,390 2,300

1,885 1,270 2,210

1,155 1,043 the dial over the magnets. It is asserted that

1,995 this telegraph is worked with the greatest

1,665

1,520 economy, that it cannot be disturbed by electric As, with batteries of the same intensity, the storms in the atmosphere, and that its average power of conducting currents of electricity celerity has been found to be 27} words per increases with the superficial area of the conminutë, with a maximum of 374.- Telegraph ductor, large wires are to be preferred to smallwires are carried over the surface of the coun- er ones upon long circuits. In working direct, try supported upon poles standing 25 to 30 a distance of over 400 or 500 miles, the line is

No.

Plain iron. Zinc-coated.

No.

Plain iron. Zinc-coated,

6
7
8
9

2,010
1,820

10 11 12 18

992
886

882 641

usually divided at some intermediate point into broken by drawing the ends together and soldertwo distinct circuits, which are connected by ing them. These men are often expert operameans of a “repeater.". This operates as a tors, and it is narrated of some of those employdouble relay, so that if the circuit be broken ed in the United States, and familiar with the on either side of the repeater, it will break the Morse system, that they can receive intelligicircuit on the other side also. The combined ble communications through the impressions circuits can thus be operated from either end made by the electric current upon the tongue as if they were one continuous wire, while the when the two wires are placed one above current of each battery has to pass only half and one beneath it.—In the extent of its telethe distance between the terminal stations. A graphic lines the United States has exceeded line can thus be extended indefinitely by in- every other country. In 1860 it was estimated terposing repeaters at proper intervals and di- that there were over 50,000 m. in operation; viding it into a number of separate circuits. and since that time the number has been largely Copper wire is a much better conductor than increased by the completion of the line from St. one of iron of the same size, and would carry Louis to San Francisco, which was opened Oct. the electric current from 5 to 6 times as far; 25, 1861, and thence to Oregon. In New York but want of strength, and frequent breakage city a great number of lines are concentrated, from its greater expansion and contraction by and the following will convey some idea of the the changes of temperature, prevent its use extent of the business carried on by the assoexcept on important submarine lines.—Upon ciated companies in their building situated at some telegraph lines in Europe and in Asia, the corner of Broadway and Liberty street. The the wires, instead of being supported upon basement contains the “delivery department poles, are buried beneath the ground. Their and the supply department or storeroom, where first cost is always heavy, and many of them all materials and instruments used on the lines have soon proved failures through imperfec- are kept on hand to be used as required. On tion in the insulation of the wires, and some- the first floor is the department for the receptimes from settling in the ground. The wires tion of messages, in the rear of which is the are best insulated by coating them with gutta operating room of the American company, a percha, and they are protected from injury by spacious apartment containing 25 instruments, saying them in pipes of lead or of earthenware, each arranged on its own table. The wires or in wooden boxes preserved by saturating the enter at the rear of the room, and pass to a wood with a solution of sulphate of copper or "switch," which is so arranged that any inchloride of zinc. Some of these lines have work- strument in the room may at pleasure be ined perfectly well for many years, but when they stantly placed in connection with any line enfail it is a matter of great expense and difficulty tering the office. From the switch wires are to discover their defective points. The insula- conducted separately to each instrument. On tion of the wires upon the posts is a matter of the second floor are rooms occupied by the much importance, and is not easily effected, for president, secretary, and other principal officers any non-conducting substance interposed be- of the company. The third floor contains the tween the wire and the post becomes a conductor operating room of the New York and Buffalo when its surface is wet with rain. Glass knobs and Erie lines. The rooms of the associated with grooves around them for securing the press are on the fourth, and the battery room wire have been made of a great variety of forms,

on the fifth floor. In the latter room are some and secured to the posts, or to the cross bars 875 cells of Grove's battery, from which all the where these are to carry several wires, by pins lines are supplied with their electric current. of wood or iron. A great improvement upon –It is estimated that in Great Britain and this is a glass cap exactly fitting over a wooden Ireland there are 40,000 m. of telegraph; in pin 17 inches in diameter, and having an outer Germany, 35,000 ; in France, 26,000; in Russia, covering of wood, saturated like the pin with 12,000; in Italy, 6,600; in Switzerland, 2,000; coal tar and pitch, to which the wire is fasten- in Denmark and Sweden, 2,000; in Turkey and ed, and which, projecting below and entirely Greece, 500. In Australia it is believed there covering the glass, keeps it dry and makes the are about 1,000 m. completed, and in India over insulation complete. Hard rubber insulators 5,000

m. controlled by the East India company. have been very extensively applied in the north- The Russians are engaged in extending a very ern states during the past five years. The de- important line from Moscow to the Pacific, vices in use in different countries for this pur- which will thus connect eastern Asia with the pose are very numerous. In forests the wires countries of Europe, and eventually by Behshould be allowed to pass loosely through the ring's straits with the American continent. supports, so that in case of a tree falling upon. This line was completed to Perm on the borthem they need not be broken; but in an open ders of Siberia, and thence over the Cral mouncountry they are usually fastened to each post. tains to Omsk on the Irtish, in 1861; thence it The wires are tightly strained as they are set is to be continued to Tomsk, and S. E. to Irand secured to the posts; and after the work kootsk, the capital of Eastern Siberia. It will is completed they require to be frequently look- then cross the Altai mountains to Kiakhta on ed after by attendants designated repairers, who the Chinese frontier, and then to Cheta on the follow the line and connect the wires when Amoor. It will then cross to Nertchinsk, to

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which point it is to be completed in 1863. to the ground, while the artificial current posFrom Oroum or some other point on the Amoor sesses too little intensity ever to overcome the one branch will extend down the river, and intervening space, and continues in the circuit. another toward the S. to a Russian port on the Similar arrangements are provided upon many Japan sea. The route from the mouth of the telegraph lines. The fire alarm telegraph is Amoor toward the American continent may be also employed to designate the exact noon by a by a short submarine cable to the island of single stroke upon the bell of the Old South Saghalien and the whole length of the island church, an exact chronometer being placed in to its southern extremity, and by a submarine the circuit and arranged so as to pass the curcable to the island of Yesso, and thence by a rent at 12 o'clock precisely. By a similar arsuccession of cables and short land lines through rangement in London a large ball is made to the Koorile islands to the S. point of Kamtchat- drop exactly at 12 o'clock from a pole erected ka; thence along the E. coast by Petropavlovsk in the Strand by the action of a current from to a point opposite Behring's island. By an- the royal observatory. The same thing is also other series of cables and land lines the tele- done at Nelson's monument, Edinburgh. In graph will then be extended by the Aleutian Paris a cannon is fired upon a similar plan. islands to America. These islands are inhab- Chronometers in observatories are also made to ited, and the line through them is doubtless run synchronously with a standard instrument much more practicable than by Behring's by means of the electric current connecting straits. The longest cable required will not, them with this.—The application of the teleit is supposed, exceed 200 m. From Russian graph to the determination of longitude has America to Oregon the intervening space is been described in the article Coast SURVEY, about 1,700 m., and on the Asiatic side from vol. v. p. 397.-Upon some railroads, as the the straits to the mouth of the Amoor the dis- Erie road especially, the telegraph is used with tance is about 2,200 m. It is believed that great advantage for regulating the running of the cost of making this connection, unless more trains from the different stations, and it is found serious difficulties are encountered with the that a single track by its aid may safe work savage tribes than is apprehended, will not ex- up to the usual capacity of two tracks.—In nuceed the cost of the Atlantic cable which was merous places telegraphs have been constructed laid in 1858.—The applications of the telegraph for private purposes, as from the workshops to have been extended to purposes never antici- the offices of manufacturing establishments; pated by those who have been most instrument- and for government purposes from the halls of al in establishing it. In 1852 Dr. William F. legislation to the printing offices, thus affording Channing and Moses G. Farmer of Boston de- the greatest facilities for the immediate printvised a system of telegraphic fire alarms, which ing of important public documents, and of was adopted in the city of Boston. Five so speeches while these are in course of delivery. called signal circuits were extended from the A system of telegraphs for the use of large cities city hall to different parts of the city, and in has been recently devised by Prof. Wheatstone, connection with these were stationed 50 signal by which a company will lease the use of a boxes attached to buildings at convenient points. small wire by the

year to individuals. For disThe door of each box being opened, a crank is tances not exceeding 20 m. a copper wire no seen with directions for the number of times it larger than a cotton thread is sufficient. Numis to be turned to convey to the central office bers of these, insulated by being wound with the number of the station and district. From thread, it is proposed to bring together into the central station 5 wires called alarm circuits one cord, and suspend as many of these as connect with the different fire bells throughout may be required from strong iron wires passed the city, the hammers of which, run by weights

, in different directions through a city upon are set in action by the telegraph itself and the houses. The latter, communicating with strike the number of the district and station of the ground at numerous points, will convey the alarm. The electric current is excited by a away all atmospheric discharges that might magneto-electric machine which is set in mo- otherwise be troublesome.—The idea of a tion by the pressure of the water with which submarine telegraph appears to have been conthe city is supplied, and the same power is em- ceived by several of the earlier electricians. ployed to wind up the weights that move the Don Francisco Salva is said to have proposed beli hammers. The bells have been rung as one as early as 1797 between Barcelona and an experiment from Portland through the tele- Palma in the island of Majorca. Experiments graph wires extending to that place, and ar- were made in India by Dr. O'Shaughnessy in rangements had been made just as the Atlantic 1839 with this object, and he insulated his wires cable ceased to work to have them set in oper- by covering them with tarred yarn, enclosing ation from the telegraphic station in London. them in split rattan, and covering this again The fire alarm also affords an incidental pro- with tarred yarn. Prof. Wheatstone in 1840 tection to the city from lightning. Large me- gave it as his opinion before a committee of the tallic surfaces being placed near the wires at house of commons that a submarine communiall the stations and connected with the ground, cation between England and France was praca stroke of lightning upon the wires will leap ticable. Prof. Morse, on Oct. 18, 1842, laid a across to these conductors, and pass harmlessly copper wire, insulated by means of a hempen

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