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THURSDAY, FEBRUARY 7, 1878 



THE SOCIETY OF TELEGRAPH 

 ENGINEERS 



WHEN a society which numbered 110 members at 

 the date of its first public meeting can, after an 

 existence of only six years, count 1,000 names upon its 

 books, it has at least justified its existence, and those who 

 have taken the chief part in calling it into being and 

 guiding its course, may fairly consider that the numbers 

 who have sought association with them prove that their 

 proceedings have been, at any rate, not injudicious. It 

 was, therefore, with good reason, that Dr. C. W. Siemens 

 began his address to the Society of Telegraph Engineers 

 on the occasion of his re-election to the office of President, 

 by congratulating the society on the progress made by it 

 since he addressed it in the capacity of its first President 

 on February 28, 1872. 



In these congratulations we heartily join, and we think 

 that no one will question the wisdom of the society in 

 calling back to the Presidentship a man who did so much 

 in the early days of its career to prepare the way for the 

 success since realised. 



The claim of the Society of Telegraph Engineers to 

 rank as a scientific institution cannot, however, be founded 

 upon the mere number of its members, nor even on the 

 scientific eminence of some of the names to be found in 

 the hst. Its scientific position must of course be judged 

 of by considering, not how many or who its members are, 

 but what they do in their associated capacity for the 

 advancement of science. Ample materials for forming 

 such an estimate as this are afforded by the six sub- 

 stantial volumes already published of the Journal of the 

 Society of Telegraph Engineers. These volumes contain 

 the papers communicated to the Society and reports of 

 discussions at the meetings, and in addition a consider- 

 able number of reprints or abstracts of papers published 

 elsewhere, bearing on the objects pursued by the Society. 

 As might be expected in the case of a society founded 

 primarily to promote the advancement, not of abstract 

 science, but of a branch of industrial enterprise, papers of 

 a so-called " practical " kind are the most numerous, and, 

 ifwe may judge from the reported discussions, papers of 

 this class are those which call forth the most general 

 interest at the Society's meetings. But even among such 

 papers, embodying as they usually do the results of careful 

 observation and long experience on the matters of which 

 they treat, there are few from which the student of physics 

 may not gather some hint of value. There are, however, 

 a considerable number of papers of which the scientific 

 bearing is more direct. These are papers which, dealing 

 with questions arising primarily out of the practice of the 

 telegraph engineer, treat the problems discussed from the 

 point of view afforded by the general scientific principles 

 applicable to them, or which contain results of no less 

 scientific than practical value. Among papers of this 

 class, one by Mr. Hockin (vol. v. pp. 432-459) on "The 

 Magnitude of Signals received through a Submarine 

 Cable with various Connections at each end, and the 

 best Resistance for the Recording Instrument," is spe- 

 cially deserving of mention. It contains a very masterly 

 Vol. XVII. — No, 432 



treatment of what is in reality a purely scientific problem, 

 though onewhich has very direct practical importance. And 

 here we may digress for a little in order to point out that 

 this paper of Mr. Hockin's affords an instructive illustration 

 of the mutual beneficial interaction between " theory " 

 and " practice " of which the whole history of the electric 

 telegraph is full. The telegraph is in a fuller degree than 

 most practical inventions the direct outcome of scientific 

 investigation, but when, in the progress of telegraphic 

 enterprise, the project arose of laying long submarine 

 lines, it was found that, though the general nature of the 

 electrical difficulties to be encounteried was known, yet 

 the scientific knowledge of the time was not sufficient to 

 indicate clearly the way in which they were to be over- 

 come, and from the nature of the case but little help was 

 forthcoming from empirical experience. The matter was 

 in this state when Sir William Thomson took up the 

 question of the transmission of signals through sub- 

 marine telegraph cables, and showed how the practical 

 message- carrying power ot an insulated conductor laid 

 under water is connected with the dimensions and certain 

 definite electrical qualities of the conductor and its insu- 

 lating coating. The conclusions which he arrived at 

 mathematically as long ago as 1855 have since remained 

 the foundation of all successful practice in the manufac- 

 ture of telegraph cables. Sir W. Thomson, however, 

 took account only of the properties of the cable itself, 

 whereas in the actual working of submarine telegraphy 

 very much depends upon the proper selection and 

 arrangement and adaptation to each particular cable of 

 the sending and receiving apparatus employed at the two 

 ends ; and what Mr. Hockin has now done is to give 

 a general theory which takes account of the electrical 

 properties of the instruments as well as of the cable. 

 Returning to the Journal of the Society of Telegraph 

 Engineers, we may mention a short paper by Mr. Sabine on 

 the Capacity of Accumulators Variously Combined, one by 

 Sir William Thomson on the Comparison of Electrostatic 

 Capacities, and a note by Prof. Maxwell on the Theory of 

 Lightning Conductors, among the original articles, as 

 well as Messrs. Longridge and Brooks's paper on the 

 Submergence of Telegraph Cables and Mr. Schwendler's 

 on the Theory of Duplex Telegraphy, among the reprints, 

 as examples which afford further proof that the Society, is 

 established for practical objects, is not blind to the aid to 

 be derived in the pursuit of those objects from the study 

 of scientific principles. And although we do not suppose 

 that all the 1,000 members study such papers as we have 

 referred to with great eagerness, yet the mere fact of their 

 circulation must do something to convince the most arro- 

 gantly "practical" man among them that ignorance is 

 not in all respects a ground for thankfulness. 



So far this flourishing society has professedly occupied 

 itself only with telegraphy, but there are not wanting 

 signs either in the Journal or in Dr. Siemens's address, of 

 the difficulty of separating telegraphy from other depart- 

 ments of what may be called applied electricity. Thus, 

 more than one paper has been read to the society upon 

 the application of electricity to firing niines and tor- 

 pedoes, an operation which, when successfully performed, 

 generally results in causing the persons affected to 

 dispense permanently with telegraphic communication, 

 and Dr. Siemens devotes nearly a quarter of his address 



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