1840] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



323 



power would not he transmitted from either ciiil past tlie disjunction. Even 

 slrould two l)ands be destroyed at a distance from each other and on tlie 

 same side of the track, its action would not lie destroyed, for althougli the 

 isolated portion of wheels would be dead, those on the other side of the 

 track would he in action, which, with the horizontal guide wheels, would 

 move forward tlie carriage, although, on such portion, at a diminished speed. 

 Instead of an increased outlay being required in the formation of railways, 

 on this system it is estimated that a very considerable saving will be effected, 

 as a single track will be sufficient, with sidings of dead wheels at the termi- 

 nation of the several jiortions into which a long line would be divided. In 

 crossing valleys, a framing of piles to sup])ort the bearing wheels would be 

 quite sufficient, and the road might be left quite open between each line of 

 wheels, as it would be impossible for the carriage to quit the track, and 

 therefore no necessity for making a solid read for safety sake. As this sys- 

 tem is so novel and rei'ohtl ionarij in its mode of action, it will of course meet 

 with. numerous opponents who are interested in the i)resent state of things ; 

 such as are not wedded thereto, or can admit the possibility of a total change 

 in tlie system, we would advise to pay a visit to the Polytechnic Institution 

 in Regent Street, where working models of this invention may be inspected. 



THE ELECTRIC TELEGRAPH. 



From the fifth Report of the Select Committee on RoUwoy^f. 



As everything connected with the operations of a power the development 

 of which is calculated in its progress to effect very great changes in our social, 

 commercial, and perhaps political condition, must be viewed with no incon- 

 siderable interest, we propose to give, from time to time, condensed but com- 

 plete abstracts of such portions of the report as we think best calculated to 

 arrest pulilic attention. 



The first evidence taken before the committee relative to the magnetic 

 telegraph, for which a patent has been taken out by Messrs. Cooke and 

 AVheatstone, and which is now in operation between West Drayton and Pad- 

 dingtou, on the Great Western line of railroad. As it would be impossible 

 without a representation of the dial and apparatus, to impart a distinct notion 

 of the manner in which intelhgence is conveyed from one station to another, 

 suffice it to say that the communication is effected by metallic wires made to 

 operate upon fine magnetic needles which point to 20 letters of the alphabet 

 marked upon the dial, being acted upon by electrical currents passing through 

 coils of wire placed immediately behind them. 



According to the information contained in the evidence of Mr. C. \yiieat- 

 stone, professor of experimental philosophy in King's College, there is no 

 necessary connexion between this species of communication and railroads. 

 On the contrarv', it can be established on a common road, or even where no 

 road exists, though a railroad, in consequence of the continuity of property 

 which it possesses, is best adapted for the experiment. In answer to a ques- 

 tion, " whether (in the event of the Great Western Railway being finished 

 from London) the telegraph could be carried through the whole way ? " Mr. 

 'Wheatstone replied, that he believed it could be done, and with but little 

 multiplication of power, inasmuch as late experiments had shown, contrary 

 to former opinions, that to send an electric current to any considerable extent, 

 there was no need of a strong battery, a weak one in fact being quite suffi- 

 cient, provided it consisted of a number of elements proportionate to the 

 distance. The communication between London and Bristol might require 

 some intermediate stations at very considerable distances, though bis own 

 opinion was that they would not be required. From experiments which ho 

 made some years since, he ascertained that electricity travelled through a 

 copper wire at the rate of about 200,000 miles in a second, being 8,000 miles 

 quicker than the rate at which light passes during the same period. 



Mr. Wheatstone states the advantages which the electric possesses over 

 the ordiuary telegraph as follows : — " It will work day and night, but the 

 ordinary telegraph will act only during the day. It will also work in all 

 states of the weather, whilst the ordinary telegraph can be worked only in 

 fine weather. There are a great many days in the year during which no 

 communications can be given by the ordinary telegraph, and besides, a great 

 many coimnuuications are stopped before they can be finished, on account of 

 changes in the state of the atmosphere ; no inconveniences of this kind would 

 attend the electrical telegraph. Another advantage is, that the expense of 

 the several stations is by no means comparable to that of the ordinary tele- 

 graph ; no look-out men are required, and the apparatus may be worked in 

 any room where there are persons to attend to it. There is another advant- 

 age which the electric possesses over the ordinary telegiaph, viz., the rapidity 

 with which the signals may be made to follow each other. 30 signals may 

 be made in a minute, a number which could not be made by the ordinary 

 telegraph. There is one thing I will take the opportunity to mention. I 

 lia\e been confining the attention of the committee to the telegraph now- 

 working on the Great Western Railroad, but having lately occupied myself in 

 carrying into eft'ect numerous improvements which have suggested themselves 

 to rac, I have, conjointly with Mr. Cooke, who has turned bis attention 

 greatly to the same subject, obtained a new patent for a telegraphic arrange- 

 ment, which I think will present very great advantages over that which at 

 present exists. It can be applied without entailing any additional expense of 

 consequence to the line now laid down, it lieing only neccssarj- to substitute 

 tlie new for the former instruments. This new apparatus requires only a 



single pair of wires to effect all which the present one does with five, so that 

 three imlependent telegraphs may be immediately placed on the line of the 

 Great Western. It presents in tlie same place all the letters of the alphabet, 

 according to any order of succession, and the apparatus is so extremely 

 simple, that any person, without any previous acquaintance with it, can send 

 a communication, and read the iuswer." 



.Vccording to the evidence of Mr. Alexander Saunders, secretary to the 

 Great Western Railroad Company, the expense of laying down the iron tubes 

 through which the magnetic wires pass, and completing the telegraphic line, 

 was from 250/. to 300/. per mile. To a question as to whether all the ad- 

 vantsges which were expected had been derived from the magnetic telegraph, 

 tliis gentleman replied, " I think we have scarcely had it in a state to say 

 that we have derived all the advantages which were contemplated from it, 

 because between West Drayton and Paddington we have very little induce- 

 ment to work the telegraph separately for that part ; it had much more refcj- 

 rence to the more distant stations, and the communications of one line with 

 others, or to communications between places on the line where short and 

 long trains together are running upon the same portion of railroad. As yet 

 we have had no practical benefit of that description, but it has enabled us to 

 ascertain that the telegraph perfectly perforins all the duty that was expected 

 of it. As far as it goes it works perfectly true, and if it work as well when 

 the whole line is completed, I fully anticipate all the useful residts contem- 

 plated from it." 



Used with a view to commercial purposes, Mr. Saunders admitted that the 

 sole possession of the magnetic telegraph would give the Great Western com- 

 pany a great advantage over the rest of the public, who could not, and as he 

 conceived ought not to have any remedy, inasmuch as the company were the 

 sole proprietors of the land, and would be at the entire expense of laying 

 down the line of telegraph. If the Government chose to have a line of tele- 

 graph alone the Great Western Railroad, he did not see any objection, pro- 

 vided the company were adequately paid for the use of their land, and that 

 the line should be used for Government purposes only. A restriction of the 

 use of the telegraph by the company solely to matters relating to the railway, 

 and prohibiting the transmission of other intelligence, would prevent the com- 

 ])aiiy from laying down the line. He also thought it would be a great hard- 

 ship if an expenditure had been incurred by any company in laying down a 

 line under the expectation that they were to derive a benefit from it, whether 

 in transmitting railway or general information, that they should be compelled 

 to permit another company to lay down another telegraph on their line. 



Mr. Wheatstone, observing upon the expense, said the cost of the present 

 experiment has exceeded 2.50/. per mile. We will assume that it cannot 

 safely be reduced, though I think with more experience that it might be. If 

 we consider that the cost of laying down the whole telegraphic line from 

 London to Bristol will be only the cost of one mile of tlie railroad itself, the 

 expenditure will not ajipear great, considering the lienefits to be obtained ; 

 this is less than one per cent, on the original estimate of the expenditure. 

 Now with respect to tlie proposed Government line. The principal expense 

 of laying down the telegraph line is, in fact, the iron tulie, and the other 

 things connected with it. The mere cost of the wires is very little, not more 

 than 6/. or 11. per mile each ; as many wires as you please may be put in the 

 same tube, consequently, supposing an iron tube to be laid down hence to 

 Portsmouth, if wires for three distinct lines were enclosed within it, the ex- 

 pense of each line, considered separately, would be very considerably dimi- 

 nished. One line might be appropriated for the railroad purposes alone, 

 another for general commercial intercourse, and a third for the exclusive use 

 of Government. There would be no difficulty if the Government have a 

 telegrajibic line thus associated with others to make the terminations in their 

 own offices, — from the Admiralty in London, for instance, to any office be- 

 longing to the same department at Portsmouth, so that information might be 

 sent without communicating with any person but their own clerks. If this 

 plan was adopted, it would do away with every objection which has been 

 made with regard to the injury a private company would do the public by 

 having the conclusive means of intelligence in their own hands, and I am sure 

 any railway company would enter willingly into an arrangement by which the 

 Government might possess an exclusive line, at a very moderate expense- 

 much below that at which they could lay it down themselves. If the new 

 telegraph of which I have spoken succeeds — and it has succeeded perfectly so 

 far as experiments have yet been tried — we might place three telegraphs in 

 connexion with the six wires now used on the Great Western Railway ; and 

 these might be applied, as I have said before, to three specific purposes — one 

 exclusively for railway purposes ; another, to be let to any persons w ho choose 

 to avail themselves of it ; and another for Government objects." 



In answer to some questions, Mr. Wheatstone said, that if Government 

 feared that any third person might, by means of portable instruments, be- 

 come acquainted with their messages, they should communicate in cypher, of 

 which an extremely safe and simple mode had been devised, enabling a per- 

 son to communicate with a thousand correspondents so as that it would be 

 impossible for any one of them to read what was intended for another. With, 

 respect to the time the apparatus would continue without requiring renewal, 

 he could not say. It depended upon the tubes being kept water-tight, as the 

 wires in that case would remain uninjured for an indefinite period. The wear 

 and tear of the telegraph apparatus from London to Bristol would be far less 

 expense than the wear and tear of the railroad for one mile. 



There is one suggestion with respect to the use of the telegraph for rail- 

 road purposes which should not be overlooked, being of the greatest import- 



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