

hazed upon Electromagnetic Theory. 585 



not the complete answer to the question: "What is Bohr's 

 theory ? " given in another place in the same paper, where 

 Dr. Adams says : " In fact Bohr's theory is based on the 

 two hypotheses of the existence of stationary states, and this 

 frequency condition," referring* to the equation € m — e n = hv? 

 Stated in this form there are cogent reasons for the general 

 validity of the theory, but the same proofs apply with equal 

 force to any other form of atomic model that satisfies these 

 two hypotheses. The valuable results already obtained in 

 the generalized theory need not, therefore, be abandoned 

 because they are construed to apply with equal force to a 

 different form of atomic model. The abandonment of rings 

 of electrons from an atomic model does not seem to be so 

 revolutionary when view r ed in the light of these facts. The 

 investigations in the Bohr theory have been so generalized 

 by the use of the theory of: probabilities applied to the 

 different states of the atom that the result has taken on a 

 statistical aspect, and does not depend very intimately upon 

 a particular form of model. 



The form of model to which the Saha theory points not 

 •only fulfills these two hypotheses but also possesses other 

 qualities of a totally different nature that seem to throw 

 some light upon phenomena hitherto obscure. So long as 

 there is strict adherence to the Bohr model, an understanding 

 of phenomena on the basis of electromagnetic theory w T ill 

 remain difficult, if not impossible. Throughout these inves- 

 tigations the fundamental assumption is that electromagnetic 

 theory is valid at all points, and is not to be set aside at any 

 point. 



VII. 



Model of the Hydrogen Atom. 



To withhold suggesting a form of atomic model which is 

 in harmony with electromagnetic theory until all the pro- 

 blems connected with its action have been rigorously worked 

 out by means of the theory would be equivalent to with- 

 holding it indefinitely, for the problems that arise are too 

 many for one individual to expect to handle. It is entirely 

 legitimate to state the case, making good use of the informa- 

 tion that has been rigorously proved and using approxi- 

 mations in oilier instances, always with the understanding 

 that these are subject to revision when the rigorous solution 

 is forthcoming. That is to say, an element of speculation as 

 to what the theory is likelv to yield later is unavoidable at 



Phil. Mag. S. 6. Vol. 42. No..250. Oct. 1921, 2 R 



