388 Rollins — Cathode Stream and X- Light. 



In working with X-light tubes I appeared to get the spec- 

 trum of hydrogen in the cathode stream though other gases 

 were in the tube. Therefore, before we reach the ultimate 

 units of which the seventy-five or more elements are com- 

 posed, we must seek more powerfully disruptive forces than 

 those in the cathode stream. The so-called ultimate, indi- 

 visible corpuscles of this stream cannot be the final units 

 because they have a familiar spectrum ; vibrating in too many 

 ways at approximately the same temperature. 



The experiments published by Trowbridge in this Journal 

 for September are the most important contribution to celestial 

 physics since Kirch hoff proved the law of exchanges and told 

 the nature of the Fraunhofer lines. Trowbridge always 

 obtained the spectrum of water vapor in the cathode stream 

 when a condenser was used. Therefore the cathode stream 

 particles are not necessarily elementary. If such minute parti- 

 cles are compound, it shows that when elements combine, it is 

 not their atoms which unite to form new molecules ; the com- 

 bination is far more intimate, a union of the particles of which 

 atoms are composed. Long before we reach the heart of 

 nature the present ultimate corpuscles will look to us more 

 complicated than a wilderness of solar systems. 



The X-Rays. 



1. Rontgen considers them longitudinal vibrations in the 

 ether. 



2. Jan man n believes they have also a transverse component. 



3. Groklhammer stated they were short transverse vibrations 

 differing from light only in size. 



4. Stokes advanced a theory of irregular pulses in the ether, 

 partly positive, partly negative. 



5. J. J. Thomson has modified Stokes' theory. He believes 

 when a cathode stream particle is stopped, its charge performs 

 a single oscillation, giving rise to a pulse in the ether. 



6. Michel son has suggested that X-rays may be ether vor- 

 tices. 



7. Several physicists believe they are flights of material 

 particles. 



This list of great names might easily be made longer. Yet 

 what do we know of the true nature of X-light? Nothing. 



I shall make a few suggestions and describe one or two 

 experiments : 



J. J. Thomson has accepted most of Wei chert's views of 

 the cathode rays, and Stokes' ideas of the X-rays. He believes 

 when a corpuscle is stopped, there arises in the ether a pulse 

 whose thickness is equal to the diameter of a corpuscle. These 

 pulses are the X-rays. According to this theory the thickness 

 of the radiant area on the target from which X-light arises 



