May 23, 1895] 



NATURE 



75 



section being something like an H, and has the wire 

 wound longitudinally in the two grooves. Wilde, who 

 may be said to have taken the first step in the direction 

 of the evolution of the modern dynamo, combined two 

 machines with Siemens' armatures, one a small magneto, 

 the other a large machine with electro-magnets in place 

 of the permanent steel magnets. The armatures of these 

 two machines were rotated, and the current from the 

 magneto was led round the electro-magnets of the other 

 machine. In this way, the magnetic field in which the 

 armature of the large machine rotated, was very much 

 stronger than it was possible to obtain with permanent 

 magnets. 



" The technical knowledge of the production of electric 

 currents by means of mechanical power had e.xtended 

 thus far,'' says Siemens, " when I succeeded, in the autumn 

 of 1866, in obviating entirely the need of steel magnets. 

 The well-known fact that the electric current driving 

 an electro-magnetic machine (motor) is considerably 

 weakened by the induced currents produced in the wind- 

 ings of the electro-magnets, made it appear probable to 

 me that by dri\ing a properly constructed electro-magnetic 

 machine backwards, the slight magnetism remaining in 

 the electro-magnets must be considerably increased since 

 the induced currents are then produced in the same 

 direction as those due to the existing magnetism. Ex- 

 perience confirmed my conjecture. I called this new 

 kind of current-producing machine dynamo-electric, as 

 by it mechanical force is directly changed into electric 

 currents, whilst the magnetism only appears as an inter- 

 mediate product, not as the real source of the current 

 produced." 



Siemens communicated a paper on this new dynamo- 

 electric machine to the Royal Academy of Sciences of 

 Berlin, on January 17, 1867. A few weeks later, William 

 Siemens, at his brother's suggestion, communicated a 

 paper to the Royal Society on this subject. This paper 

 was read at a meetmg at which Prof. Wheatstone, who, 

 without knowing of Werner .Siemens' discover\-, had been 

 working at this question, read a paper embodying the 

 same idea. Some time afterwards it became generally 

 known that a provisional patent, which had been kept 

 secret, and which also covered this invention, had been 

 issued to the Brothers Varley in December 1866. 



It appears, therefore, that several people hit upon what 

 may be called the dynamo principle almost simultaneously. 

 From the fact, however, that Siemens was the first to publish 

 the discovery-, according to the usually accepted principle 

 introduced by .\rago, there seems no doubt that his claim 

 for priority is justified. 



This claim for priority with reference to the invention 

 of the dynamo is made again and again in several 

 addresses, &c., in the second volume. As most of these 

 papers are mere repetitions, one of another, it is very 

 tloubtful whether any good purpose is served by printing 

 more than one, since the reader becomes very tired of 

 Ijeing taken over the same ground several times. 



At the end of the second volume there are a number of 

 patent claims, &c., for meters to measure electrical 

 energy. The demand for such a meter, which should 

 combine accuracy with a moderate cost, arose directly the 

 supply of electric current for lighting and power purposes 

 became at all general. Such a demand in connection 

 with any electrical subject was always for Werner 



NO. 1334, VOL 52] 



Siemens almost a mandate, and he at once devoted a 

 good deal of time and attention to supplying this want. 



The chief interest of most of the papers is, no doubt, 

 historic ; the two last of all, however, have a special 

 interest at the present moment in this country. They 

 form an appendix to the second volume, and have refer- 

 ence to the foundation by Werner von Siemens of the 

 Physico-Technical Institution at Charlottenburg. The 

 reasons given by Siemens for the foundation of such an 

 institution in Germany apply to the case of our own 

 country at the present day, for we are still without such 

 an institution, though, through the munificence of Dr. 

 Ludwig Mond, the region of usefulness of the Royal 

 Institution is to be extended in this direction. Siemens, 

 during his long and successful career, had noticed that 

 although the general standard of scientific education was 

 probably higher in Germany than in any other country, 

 the result was to produce not so much scientific workers 

 and discoverers as teachers. 



" Scientific investigation," he says, " itself is nowhere a 

 life vocation in the State organisation, it is only a per- 

 mitted private business of the learned besides their 

 vocation, teaching business. ... It must, however, be 

 pointed out as a waste of national strength, that highly 

 gifted inquirers, talents such as only seldom come to 

 light, are hea\ily burdened with professional (? profes- 

 sorial) labours, which others would perhaps perform even 

 better, and are thereby in great measure withdrawn from 

 science itself, to which they would bear incalculable 

 service if they could give themselves up entirely to it. 

 But it is a still greater pity that so many talented and 

 highly-cultured young students find no opportunity to 

 carry- out scientific work. The unfortunate consequence 

 in most cases is that scientific labours which would 

 animate and fructify whole domains of life, remain un- 

 done, and that, in the struggle for existence, talents do 

 not develop or fall to the ground unrecognised, which 

 under more favourable circumstances would have been 

 able to perform great things to the honour and to the 

 material advantage of the country. It is to be feared 

 that the advantage ... of better scientific instruction 

 and of more widely-spread scientific culture, will soon be 

 lost ... if it is not supported by State organisations. 

 These organisations would have to fulfil a double purpose, 

 to advance scientific inquiry generally and to aid industry 

 by means of the solution of scientific technical problems 

 and questions which are essential to its development. 

 ... In order to make clear the great importance which 

 such an institution, well supplied and liberally endowed, 

 would have on the development of industry-, a short 

 retrospect of the history of this development is quite 

 suflficient. We see this everywhere associated with per- 

 sons and institutions, where it was possible by specially 

 favourable conditions that scientific researches went 

 hand-in-hand witli their technical applications. The 

 scientific light, which in consequence led technical com- 

 binations and methods, gave such institutions such a 

 preponderance over others that the cost of experiments 

 was not only covered by the higher commercial results, 

 but also whole branches of industry were radically trans- 

 formed b\- them, and new ones of great importance 

 created. . . . This combination is most easily realisable 

 in chemical manufacture. . . . More unfavourable is, how- 

 ever, the position of the trades depending on mechanical 

 bases. Exact physical experiments demand much more 

 costly instruments and specially-prei)ared roorns. ... If 

 the State, therefore, confines itself as heretofore only 

 to looking after instruction, the mechanical crafts 

 necessarily lag behind the chemical in their develop 

 ment." 



