<o.\[F. coxrr.MroR.iRy .ini-.ixci-s ix physics -ix 657 



wmilil ho cxiHVled to emit; for an elorlrical cliarRC pcrfonniriK ,t 

 |H'ri(Hlir motion should, accordinj; to the fiindaincntal doctrines of 

 the elect roniai;netic theory, lie the origin of a stream of radiation 

 with jH^riod e<nial to its own. The symbol v stands for the frequency 

 of the radiation which the atom does emit in passing between two 

 a<!jaccnt Stationary States. According; to (19), this actual fre- 

 (|uency is more nearly e(|ual to the expected frequency, the more 

 remote these two adjacent Stationary States are from the normal 

 .State; and in the limit, actual frecjuency and expected frequency 

 merge into one. The numerical value of the constant R is just such 

 as to bring about this relation. 



Here again we have a curious nunuriial at;rii'imrit wliicli, like 

 the other correlatetl fact that the angular momentum of the electron 

 in the nth orbit is nli 2jr, may by itself be merely a coincidence; but 

 this one has a much greater inherent appeal. We ha\e relinquished 

 the expectation that the electron, cruising around the nucleus in a 

 c\clic path, will send forth radiation of the frequency of its own 

 revolutions, as every inference from the laws of electricity indicates 

 that it should; but here is a case — e\en if it is only a limiting case — 

 in which the frequency emitted from the atom agrees with the one 

 which we should expect. Generally there is discord; but in the lim- 

 iting case there is consonance. Does this not suggest that the desired 

 Principle may be one which in a limiting case merges with the classical 

 theor>- of electricity — possibly, indeed, nothing less than the founda- 

 tion of a general theor>- of electricity.-, of which the classical theory 

 expresses only a special case? 



Let us review our situation. 



Having supposed for hydrogen an atom-model consisting of a nucleus 

 and an electron; 



Ha%ing supposed that these revolve around their common centre of 

 mass according to the laws of dynamics, but without spetuling any 

 energy in radiation; 



Having supposed in particular that they revolve only in circular 

 orbits, and only in such circular orbits as yield for the atom-model 

 the energy-values — /?// ;;- measured by experiments upon the .Sta- 

 tionary-States; 



Having tracwl these "permissible" circular orbits. 



We have found that they are distinguished from all the other cir- 

 cular orbits by at least three peculiar features (viz., the features ex- 

 pressed by the equations /) = ;;/; 2t. and / = «//, and Lim io = Lim v). 



We do not know- that there is any revolving electron at all. We 

 know only that if all our suppositions be correct, the consequence^ 



