ON STANDARDS FOR USE IN ELECTRICAL MEASUREMENTS. 129 



of members who expressed a preference for the name ' International ' was 

 greater than the number declaring in favour of any other name, but that 

 he thought that the Committee would accept whichever of the first three 

 suggestions commended itself to the French Committee appointed to deal 

 with the matter. 



During the year Dr. Muirhead has remeasured his standard condenser. 

 He now finds as the capacity of a condenser constructed twenty-three 

 years ago to represent '1 microfarad (B.A.U.) the value "09998 micro- 

 farad. 



Tests have been made during the year on the 1-ohm and 10-ohm 

 standards of the Association. These are still being continued. The 

 100-ohm and 1000-ohm standards have now been delivered, and the 

 tests will be shortly proceeded with. Some experiments were made as 

 to the amonnt of heating in the coils produced by the current used for 

 testing. These are detailed in Appendix II. Further valuable informa- 

 tion on this point is contained in Mr. Griffiths' paper on ' The Value 

 of the Mechanical Equivalent of Heat.' ' 



The Comruittee think it desirable that they should be in a position to 

 complete the set of resistance standards of the Association, and recom- 

 mend, therefore, that they be reappointed, with a grant of 25Z., that 

 Professor G. Carey Foster be Chairman, and Mr. R. T. Glazebrook 

 Secretary. 



APPENDIX I. 



Supplementary Report of the Electrical Standards Committee of the 



Board of Trade. 



To the Right Hon. A. J. Mundella, M.P., 

 President of the Board of Trade. 



Subsequently to the presentation of our former report to Sir Michael 

 Hicks-Beach, in July 1891, we were informed that it was probable that 

 the German Government would shortly take steps to establish legal 

 standards for use in connection with electrical supply, and that, with a 

 view to secure complete agreement between the proposed standards in 

 Germany and England, the Director of the Physico-Technical Imperial 

 Institute at Berlin, Professor von Helmholtz, with certain of his assistants, 

 proposed to visit England for the purpose of making exact comparisons 

 between the units in use in the two countries, and of attending the meet- 

 ing of the British Association which was to take place in August in 

 Edinburgh. 



Having regard to the importance of this communication it appeared 

 desirable that the Board of Trade should postpone the action recom- 

 mended in our previous report until after Professor Helmholtz's visit. 



That visit took place early in August, and there was a very full 

 discussion of the whole subject at the meeting of the British Association 

 in Edinburgh, at which several of our number were present. The meet- 

 ing was also attended by Dr. Guillaume, of the Bureau International des 

 Poids et Mesures, and Professor Carhart, of the University of Michigan, 



' Phil. Trans., 1893. 

 1893. K 



