1881.] 



President's Address. 



51 



Perhaps in no subject is the necessity of uniform system of standards 

 so striking as in electricity. This science, both in its practical appli- 

 cations, such as telegraphy, and in the great natural problems of terres- 

 trial magnetism and atmospheric, electricity, refuses to recognise any 

 artificial divisions of the surface of the globe, whether ethnological 

 or political. It rarely happens, in operations undertaken on so large 

 a scale as the study of electricity and its industrial applications, that 

 an opportunity presents itself of arranging for concerted and har- 

 monious action through a period extending to a distant future. Before 

 a branch of industry has attained sufficient importance to claim 

 international recognition, it has usually gone through the process of 

 considerable development in different countries ; and in each of these 

 developments it has often received a stamp of local character which 

 makes it difficult to reduce the whole to one uniform system. But in 

 the case of electricity there were fortunately present special circum- 

 stances which facilitated the adoption of uniform standards. Foremost 

 among these was the fact that the development of its practical appli- 

 cations, in other departments than telegraphy, were so recent that it 

 was not too late to legislate for it as though it were but just about to 

 begin. Secondly, the international character of telegraphy, and the 

 fact that the manufacture of its apparatus had always been confined to 

 the great centres of civilisation, had both tended to limit the 

 number of existing systems of measurement, and prevented that 

 multiplicity of standards which would certainly have arisen had such 

 manufacture been carried on in numerous and in isolated localities. 

 But by far the most important influencing circumstance was the 

 happy idea due to the British Association of adopting standards 

 based on absolute measures. The Association did not allow the 

 idea to remain barren ; but, through the instrumentality of its Com- 

 mittee on Electrical Standards, it gave to the world the admirable 

 units of the Ohm, the Volt, and the now re-christened Weber ; and the 

 eminent men who formed that Committee may now point with honour- 

 able satisfaction to the fact that the Electrical Congress decided 

 unanimously to recommend for universal acceptance those units which 

 that Committee so early adopted. 



With the single exception of the unit of current which, in order 

 to avoid an ambiguity in the signification of Weber, receives the title 

 of Ampere, the names are left substantially without change. 



The adoption of these units for international use is to be preceded 

 by a new and more careful redetermination of the ohm at the hands 

 of the great physicists of all nations. And it is intended that this 

 redetermination shall result in a standard for general adoption. Thus 

 electricity will be the first of the practical sciences to be freed from 

 all difficulties due to local standards ; and it is to be hoped that this 

 example may be followed in other sciences concerned with practical life. 



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