﻿332 Dr. N. Bohr on the Series Spectrum of 



representing the gyroscopic connexion between the two atoms, 

 Balmer's law may be accounted i'or, and the demonstration 

 is considered of sufficient importance to repeat in full. 



The frequency of vibration of the positive electron in the 

 atom is 43*55 times slower than that of the negative electron, 

 giving long waves which may be considered as heat 

 radiation. 



7. This atom is capable of response to any frequency of 

 light, because there are precessional frequencies produced in 

 the atom proportional to those of the impressed force. Xu 

 form of atom capable of resonance at fixed frequencies only 

 can possibly account for the experimental facts connected 

 with the photo-electric effect. It is suggested that light 

 pressure upon the electron, when the light falls at an angle 

 with the plane of the orbit, is responsible for inducing a 

 precessional variation of double the light frequency. 



XXXVI. On tJie Series Spectrum of Hydrogen and the 

 Structure of the Atom. 



To the Editors of the Philosophical Magazine. 

 Gextlemex, — 



IN the January number of this magazine Dr. H. Stanley 

 Allen has published two interesting papers in which he 

 considers the effect on the series spectrum of an element if 

 the central nucleus of the Rutherford atom has, besides its 

 electric charge, the properties also of a small magnet. In 

 the first paper, it is shown that a nuclear magnet under 

 certain assumptions might give rise to a number of different 

 series of lines, instead of the single series of lines to be 

 expected if the nucleus consists simply of a point charge. 

 It is shown, however, that a magnetic field of the order of 

 magnitude which may be assumed to occur in the actual 

 atoms will be much too small to account for the different 

 series of lines which have been observed in the spectra of the 

 elements. In the second paper, the formula? deduced in 

 the first are applied to the hydrogen spectrum, and it is 

 attempted by the help of the hypothesis of a nuclear magnet 

 to explain the very small deviations from the Balmer law 

 which have been observed by Mr. Curtis in his recent 

 accurate measurements of the wave-length of the hydrogen 

 lines. The moment of the nuclear magnet is found to be 

 approximately equal to that of 5 magnetons. The import- 

 ance of this result, if correct, is easily seen ; but it would 

 appear that some of the deductions made by Dr. Allen are 

 difficult to justify. 



