60 Doublets and Triplets in the Spectrum. 



with Cd and other substances *, and therewith the discussion 

 about the ratio between mass and charge of the ions in 

 Lorentz's theory. It is very probable that these "ions" 

 differ from the electrolytical. It is true that by means of 

 the latter many phenomena can be interpreted, as also is done 

 in a paper by Richarz t, where, e. g., the molecular mag- 

 netism is explained by the motion of the ions, but the high 

 value of e/m which I have found makes it extremely im- 

 probable that we have to deal with the same mass in the 

 two cases. And Lodge J has even pointed out in an extremely 

 interesting paper that my value of e/m can be explained 

 without the necessary motion of any " matter" at all. 



Appendix. — On communicating the observations of this 

 paper to Prof. Lodge, he most kindly informed me that he had 

 already seen some of them himself. Especially he had seen 

 the doubling of the lines and shown them at the Royal Society 

 soiree on May 20. He, however, did not suppose it to be 

 a real doubling of the line, but thought it to be a broadening 

 and a reversal. I have given my reasons (the chief being the 

 circular polarization over the whole width) for thinking that 

 I observed a real doubling. I am confirmed in this opinion 

 because it corroborates the observation of the perpendicular 

 polarizations of the middle and of the edges of the triplet a 

 (§ 10). As Prof. Lodge does not mention that he observed 

 this last phenomenon, and as my point of view is different 

 from his, his object not being in the first place to test 

 Lorentz's theory, I publish the paper in its original form, 

 though it turns out that part of its contents has been observed 

 by both of us independently §. 



Amsterdam, Jane 4. 



* I have experiments in progress (measurements of the photographed 

 magnetized spectrum) by which I hope to be able to obtain fairly accurate 

 values of the magnetic change. 



t Wied. Ann. lii. p. 385 (1894). 



| 'The Electrician,' Mar. 12, 1897. 



§ Disclaimer by Prof. Lodge. 



Having been asked to exhibit Prof. Zeeman's discovery at the Royal 

 Society soir6e I arranged apparatus to obtain it more powerfully, and 

 thereby saw the new effects ; but without any intention of trespassing on 

 the prerogative of the discoverer. 



What I saw concerning polarization was that, when looking across the 

 lines of force, a nicol brought out the doubling (or tripling or quadrupling 

 as the case might be) more sharply, no doubt by quenching the residual 

 light ; and that it restored the original appearance of the line when 

 rotated through 90°. I mention this here as partially confirming 

 Prof. Zeeman's most interesting and much more complete investigation, on 

 the theoretical aspect of which at present I offer no further opinion. — 

 Liverpool, June 6. 



