ON ATMOSPHERIC ELECTRICITY 215 



will then discharge itself either towards the earth or through the rare- 

 fied air in the shape of an aurora. At these points the rarefied air 

 probably heaps itself up to a greater height than elsewhere, which 

 would explain the great height at which auroras are sometimes observed. 



The equilibrium which existed previously at the equator would also 

 be destroyed by the absence, at this point, of the primitive charge in 

 the exterior atmosphere, and the earth would have a tendency to dis- 

 charge itself towards the exterior atmosphere. Owing to the difference 

 in the conditions at this point, this tendency will be apt to show itself 

 by the storms which arise oftenest in the equatorial region. Thus the 

 electricity of the earth would tend to circulate in the same way as the 

 air from the equator to the poles and conversely. 



But I do not intend to insist upon this theory here; I wish simply 

 through it to bring out the importance of establishing on the whole 

 surface of the globe a system of general observations on atmospheric 

 electricity. Even if the theory is false, it is only by observation that 

 the truth can be attained. In my opinion, it is almost unworthy of the 

 advanced state of our sciences to-day, that it should be at present impos- 

 sible for us to indicate accurately the origin of the energy which mani- 

 fests itself in auroras and storms. For I have pointed out above that 

 it is necessary to give up explaining these phenomena by the hypothesis 

 of the production of electricity by evaporation. 



I propose therefore that from this section of the Congress a com- 

 mittee be formed to examine what is to be done in order to establish 

 on the whole earth, and especially in the polar regions, a systematic 

 series of observations on atmospheric electricity. 



EDITORIAL NOTE. International Commission of Electricians 



[Professor Rowland sailed from New York, October 14, to attend an 

 international commission of electricians, then about to assemble in 

 Paris. Professor John Trowbridge of Cambridge sailed about the same 

 date. These two gentlemen were selected to represent the United 

 States government by the Department of State Congress having made 

 provision for the appointment of two civilian commissioners. 



This official commission is the outgrowth of the congress of electri- 

 cians which was held a year ago in Paris. That body requested the 

 French government to invite other nations to unite in constituting 

 three international commissions for the study of certain specified 

 problems, namely: 



I. A re-determination of the value of the ohm. 



