436 



NATURE 



[September 4, 1890 



has thus been already, in a measure, fulfilled, important progress 

 is being continuously made by the practical electrician in deve- 

 loping and perfecting the arrangements for the generation of the 

 supply, its efficient distribution from centres, and its delivery to 

 the consumer in a form in which it can be safely and conveniently 

 dealt with and applied at an outlay which, even now, does not 

 preclude a considerable section of the public from enjoying the 

 decided advantages presented by electric lighting over illumina- 

 tion by coal-gas. Yet our recent progress in this direction, en- 

 couraging though it has been, is insignificant as compared with 

 the strides made in the application of electric lighting in the 

 United States, as may be gauged by the fact that, while in 

 America the number of arc lamps in use, in April of this year, 

 was 235,000, and of glow-lamps about three millions, there are 

 at present only about one-tenth the number of the latter, and one 

 hundredth the number of arc lamps, in operation in England. 



In some important directions we may, however, lay claim to 

 rank foremost in the application of the electric light ; thus, our 

 large passenger-ships and our war-ships are provided with efficient 

 electrical illumination ; to the active operations of our Navy the 

 electric light has become an indispensable adjunct ; and our 

 system of coast defence, by artillery and submarine mines, is 

 equally dependent, for its thorough efficiency, upon the applica- 

 tions of electricity in connection with range-finding, with the 

 arrangement and explosion of mines, and with the important 

 auxiliary in attack and defence, the electric light, which, while 

 so arranged, at the operating stations, as to be protected against 

 destruction by artillery-fire and difficult of detection by the 

 enemy, is available at any moment for affording invaluable in- 

 formation and important assistance and protection. 



Other important applications of the electric light, such as its 

 use as a lighthouse-illuminant, for the lighting of main roads in 

 coal-mines, where its value is being increasingly appreciated, and 

 even for signalling purposes in mid-air, through the agency of 

 captive balloons, are continually affording fresh demonstrations 

 of the value of this particular branch of applied electric science. 



At the Electrical Exhibition at Vienna in 1883, where, not 

 long before the lamented death of Siemens, I had the honour of 

 serving as one of his colleagues in the representation of British 

 interests, the progress which had been made in the construction 

 of electrical measuring instruments since the French Exhibition 

 and the Electrical Congress, two years before, was very con- 

 siderable. The advance in this direction has been enormous 

 since that time ; but although the practical result of Thomson's 

 and of Carlew's important work has been to supply us with 

 trustworthy electrical balances and voltmeters, while efficient in- 

 struments have also been made by other well-known practical 

 electricians, we have still to attain results in all respects satisfac- 

 tory in these indispensable adjuncts to the commercial supply and 

 utilization of electric energy. 



In connection with this important subject the recent completion 

 of the Board of Trade standardizing laboratory, established for 

 the purposes of arriving at and maintaining the true values of 

 electrical units, and of securing accuracy and uniformity in the 

 manufacture of instruments supplied by the trade for electrical 

 measurements, may be referred to with much satisfaction as a 

 practical illustration of official recognition of the firm root which 

 the domestic and industrial utilization of electric energy has 

 taken in this country. 



The achievements of the telephone were referred to by Siemens 

 in glowing terms eight years ago ; but the results then attained 

 were but indications of the direction in which telephonic inter- 

 communication was destined speedily to become one of the most 

 indispensable of present applications of electricity to the purposes 

 of daily life. Preece, in speaking at Bath, two years ago, of the 

 advances made in applied electricity, showed that the impedi- 

 ments to telephonic communication between great distances had 

 been entirely overcome ; and now, although considerably behind 

 America and France in the use of the telephone, we are rapidly 

 placing ourselves upon speaking terms with our friends through- 

 out the United Kingdom. The operations of the National 

 Telephone Company well illustrate our progress in telephonic 

 intercommunication: that company has now 22,743 exchange 

 lines, besides nearly 5000 private lines ; its exchanges number 

 272, and its call-offices 526. The number of instruments under 

 rental in England has now reached 99,000 ; but, important as 

 this figure is compared to our use of the telephone a very few 

 years ago, it sinks into insignificance by the side of the number 

 of instruments under rental in America, which at the beginning 

 of the present year had reached 222,430, being an increase of 



16,675 over the number in 1889. Only thirteen years have 

 elapsed since the telephone was first exhibited as a practically 

 workable apparatus to members of the British Association at the 

 Plymouth Meeting, and the number of instruments now at work 

 throughout the world may be estimated as considerably exceeding 

 a million. 



The successful transmission of the electric current, and the 

 power of control now exercised over the character which elec- 

 trically-transmitted energy is made to assume, are not alone 

 illustrated by the efficiency of the arrangements already developed 

 for the supply of the electric light from central stations. Siemens 

 dwelt upon this subject at Southampton with the ardent interest 

 of one who had made its development one of the objects of his 

 energetic labours in later years, and also with a prophet's prognos- 

 tications of its future importance. In speaking of the electric 

 current as having entered the lists in competition with compressed 

 air, the hydraulic accumulator, and the quick-running rope 

 driven by water-power, Siemens pointed out that no further loss 

 of power was involved in the transformation of electrical into 

 mechanical energy than is due to friction, and to the heating of 

 the conducting wires by the resistance they oppose, and he showed 

 that this loss, calculated upon data arrived at by Dr. John 

 Hopkinson and by himself, amounted at the outside to 38 per 

 cent, of the total energy. Subsequent careful researches by the 

 Brothers Hopkinson have demonstrated that the actual loss is 

 now much less than it was computed at in 1885 ; as much as 

 87 per cent, of the total energy transmitted being realizable at a 

 distance, provided there be no loss in the connecting leads 

 used. 



The Paris Electric Exhibition of 1881 already afforded interest- 

 ing illustrations of the performance of a variety of work by power 

 electrically transmitted, including a short line of railway con- 

 structed by the firm of Siemens, which was a further development 

 of the successful result already attained in Berlin by Werner 

 Siemens in the same direction, and was, in its turn, surpassed by 

 the considerably longer line worked by Messrs. Siemens at the 

 Vienna Exhibition two years later. Various short lines which 

 have since then been established by the firm of Siemens are well 

 known, and one of the latest public acts in the valuable life of 

 Siemens was to assist at the opening of the electric tramway at 

 Portrush, in the installation of which he took an active part, 

 and where the idea, so firmly rooted in his mind from the date 

 of his visit to the Falls of Niagara, in 1876, of utilizing water- 

 power for electrical transmission — a result first achieved on a 

 small scale by Lord Armstrong — was more practically realized 

 than had yet been the case. Since that time Ireland has 

 witnessed a further application of electricity to traction purposes, 

 and of water-power to the provision of the required energy, in 

 the working of the Bessbrook and Newry tramway, while London 

 at length possesses an electric railway, three miles in length, to 

 be very shortly opened, which will connect the City with one of 

 the southern suburbs through a tram subway, and, although 

 including many sharp curves and steep gradients, will be capable 

 of conveying one hundred passengers at a time, at speeds varying 

 j from thirteen to twenty-four miles per hour. During the past 

 year a regular service of tramcars has been successfully worked, 

 through the agency of secondary batteries, upon part of one of 

 the large tramways of North London, with results which bid fair 

 to lead to an extensive development of this system of working. 

 The application of electricity to traction purposes has, however, 

 received far more important development in the United States ; 

 at the commencement of this year there were in operation in 

 different States 200 electrical tramroads, chiefly worked upon 

 the Thomson-Houston and the Sprague systems, and having a 

 collective length of 1641 miles, with 2346 motor-cars travelling 

 thereon. Further extensions are being rapidly made ; thus, one 

 company alone has 39 additional roads, of a collective length of 

 385 miles, under construction, to be worked through the agency 

 of storage-batteries. 



The idea cherished by Siemens, and enlarged upon by him in 

 more than one interesting address, of utilizing the power of 

 Niagara, appears about to be lealized, at any rate in part ; as a 

 large tract of land has been recently acquired, by a powerful 

 American association, about a mile distant from the Falls, with 

 a view to the erection of mills for utilizing the power, which it is 

 also proposed to transmit to distant towns ; and an International 

 Commission, with Sir William Thomson at its head, and with 

 Mascart, Turrettini, Coleman Sellers, and Unwin as members, 

 will carefully consider the problems involved in the execution of 

 this grand scheme. 



NO. 1088, VOL. 42] 



