Septembee 28, 1917] 



SCIENCE 



299 



Fig. 1. 



soever upon the particle C, the latter will 

 be set into sympathetic motion, and a part 

 of the energy of the atom at the absolute 

 zero will be contributed to the particle C, 

 contrary to the most fundamental prin- 

 ciples of thermodynamics. Therefore, un- 

 less we are willing, under the onslaught of 

 quantum theories, to throw overboard all 

 of the basic principles of physical science, 

 we must conclude that the electron in the 

 Bohr atom not only ceases to obey Cou- 

 lomb's law, but exerts no influence what- 

 soever upon another charged particle at 

 any distance. Yet it is on the basis of 

 Coulomb's law that the equations of Bohr 

 were derived. 



In spite of this and other similar seri- 

 ous objections to Bohr's atomic model, I 

 should not wish to minimize the importance 

 of his work. He has been the first to pre- 

 sent any sort of acceptable picture of the 

 mechanism by which spectral series are pro- 

 duced, and especially he has traced a rela- 

 tion between two important constants of 

 nature, Rydberg's fundamental frequency, 

 and the Planck constant h which plays so 

 important a part in modern physical 

 theory. I should therefore be loath to sug- 

 gest an abandonment of the extremely in- 

 teresting leads which Bohr's theory has 

 suggested, nor do I think this necessary, 



- It ■n-ill be noted that this objection appUes 

 with equal force to the Planck oscillator which 

 maintains energy even at the absolute zero. 



for I believe that relationships similar to 

 those obtained in Bohr's theory may be ob- 

 tained, even if we substitute for the orbital 

 atom of Bohr a static atom, and, moreover, 

 I believe that by making this substitution 

 we may not only obtain a model of the 

 atom which is consistent with known chem- 

 ical facts, but also one which does not re- 

 quire the abandonment of the principal 

 laws of mechanics and electromagnetics. I 

 should state at onee, however, that I do not 

 claim for the atomic model, which I am 

 about to sketch in rough outline, the same 

 finality that I would claim, for example, 

 for the molecular model of methane which 

 I have previously offered.^ It is rather a 

 suggestion of the direction in which we 

 may work towards the solution of a prob- 

 lem of extraordinary difficulty with the 

 most hope of ultimate success. It is evi- 

 dent to any one familiar with the extreme 

 complexity of the spectra of some sub- 

 stances that many years must elapse before 

 anything approaching to a final explana- 

 tion of such baffling phenomena can be ex- 

 pected. All we can do at present is to sug- 

 gest certain directions of investigation 

 which may lead ultimately towards the de- 

 sired end. With this understanding, you 

 will not consider it too presumptuous if I 

 start by discussing not the structure of the 

 complicated system that we call the atom, 

 but rather the structure of the electron 

 itself, or, if you prefer, the structure of 

 the field of force about the electron. 



If we postulate, at small distances, the 

 nonvalidity of Coulomb's law of force 

 between the centers of two charged 

 particles, we are doing nothing that is 

 really new. In the older conception of the 

 electron as a charged sphere of definite 

 radius, the sphere being itself held together 



3 I refer here and elsewhere to my paper ' ' The 

 Atom and the Molecule," J. Am. Chem. Soc, 38: 

 762, 1916. See also Proc. Nat. Acad., 2: 586, 

 1916. 



