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SCIENCE 



[N. S. Vol. XXXI. No. 799 



don; Professor Paul Janet, of Paris; Pro- 

 fessor H. S. Carhart, of Ann Arbor, Michi- 

 gan, and Dr. F. A. Wolii, of the Bureau of 

 Standards, Washington. 



It was impossible to select a new value of 

 the Weston normal cell in terms of the ohm 

 and the ampere until the latter should be more 

 precisely defined than had been done by the 

 London Conference. Correspondence among 

 the members of the committee who were con- 

 nected with national standardizing institu- 

 tions seemed to indicate that it would be 

 impossible to agree upon the specifications of 

 the silver voltameter without further investi- 

 gation, and it was proposed by the American 

 members of the committee that a joint in- 

 vestigation to clear up, as far as possible, 

 outstanding problems on the standard cell and 

 the silver voltameter be arranged with repre- 

 sentatives of several of the national standard- 

 izing laboratories as participants. Professor S. 

 W. Stratton in his capacity as director of the 

 Bureau of Standards offered the facilities of 

 the Bureau of Standards for an international 

 investigation, and in his capacity as treasurer 

 of the International Committee on Electrical 

 Units and Standards offered to secure the 

 funds to pay the expenses of the investigation. 

 In this connection he received valuable assis- 

 tance from Mr. John W. Lieb, Jr., who 

 placed the matter before the governing bodies 

 of the American Institute of Electrical Engi- 

 neers, the National Electric Light Associa- 

 tion, the Association of Edison Illuminating 

 Companies and the Illuminating Engineering 

 Society. These four societies made appro- 

 priations of $500 each to defray the expenses 

 of the proposed investigation. Their gener- 

 osity in this matter is very highly appreciated 

 by the International Committee on Electrical 

 Units and Standards. Some smaller contri- 

 butions were also received. 



It was arranged that the proposed investi- 

 gation should be carried out at the Bureau of 

 Standards by representatives of that insti- 

 tution together with one delegate from the 

 Physikalisch-Technische Eeichsanstalt, Ber- 

 lin, one from the National Physical Labora- 

 tory, London, and one from the Laboratoire 



Central d'Electricite, Paris. The European 

 delegates, as appointed by the directors of the 

 three above named institutions, are Professor 

 W. Jaeger, Mr. F. E. Smith and Professor F. 

 Laporte. These gentlemen have had a very 

 considerable experience in work with standard 

 cells and silver voltameters, have published 

 various investigations on the same, and are 

 eminently qualified to represent their respec- 

 tive institutions and to join in the work of 

 research and deliberation upon the various 

 questions that will arise during their stay in 

 Washington. The representatives of the 

 Bureau of Standards are Professor E. B. 

 Eosa and Dr. F. A. Wolff. In addition to 

 published papers, a great deal of experimental 

 work has been done at the Bureau of Stand- 

 ards which is not yet published, which throws 

 considerable light upon the questions at issue. 



In addition to the work on standard cells 

 and the silver voltameter, a comparison is to 

 be made of the resistance standards of the 

 several national standardizing institutions. 

 The wire standards of the Eeichsanstalt, the 

 National Physical Laboratory and the Bureau 

 of Standards differed only about two parts in 

 a hundred thousand at the last intercompari- 

 son about a year ago, the standards of the 

 first two of the above institutions having 

 been fixed independently by legally specified 

 mercury ohms. It is expected that a common 

 value of the international ohm wiU be agreed 

 upon, so that no difference greater than one 

 part in a hundred thousand will exist between 

 the wire standards of the national standardiz- 

 ing institutions. 



It is confidently expected that the com- 

 mittee will succeed in coming to a satisfac- 

 tory agreement with respect to the oificial 

 specifications of the silver voltameter and the 

 Weston normal cell, and will be able to agree 

 upon a value for the latter which can be 

 recommended to all countries of the world 

 for adoption. The degree of accuracy which 

 is now obtainable in electrical measurements, 

 both in absolute measurements and in rela- 

 tive measurements, far surpasses what was 

 possible in 1893, and indeed has increased 

 greatly within the last five years. There is 



