368 PARIS CONFERENCES. 



request being preferred to the French government to 

 bring about diplomatically the assembling of an inter- 

 national conference of delegates, whose task should be 

 the establishment of a scientific system of standards 

 for electro-technology. 



Such a conference, to which Helmholtz, Wiede- 

 mann, Clausius, Kirchhoff and myself were deputed 

 by the German Empire, met in Paris in the following 

 year, and decided in principle for the absolute standard 

 system of William Weber, with the modification that 

 the c. g. s. standard, for which England had already 

 pronounced, was adopted as the standard of resistance. 

 Owing to the little accuracy however, with which 

 hitherto the absolute resistance unit of Weber could 

 be reproduced in practice, it was resolved to take as 

 a practical basis the mercury unit, which I had pro- 

 posed, and to invite the scientists of every country, 

 to ^settle experimentally the relation of the modified 

 c. g. s. unit to the then widely adopted Siemens unit. 

 As the mean of all the determinations in consequence 

 arrived at there resulted for this relation the value 

 1-06; and accordingly a column of mercury of 1 square 

 millimetre in cross section and 106 centimetres long 

 at C. named "Ohm" was established at the final 

 conference in the year 1884 as the international 

 legal unit of resistance. In like manner the names 

 of meritorious physicists were selected for the re- 

 maining units of the system; it is however to be 

 regretted that the name of William Weber, the creator 

 of this absolute standard system, was passed over, 



