MIRACLES OF SCIENCE 



Professor Hale thinks that the magnetic field may 

 be due to the rapid flow, in a vortex current, of 

 negative ions from the hotter gases at the circum- 

 ference of the spot towards the cooler gases at the 

 center. 



A further interest attaches to the Zeeman effect 

 (whether manifested in the laboratory or in the sun) 

 from the fact that it demonstrates the close relation- 

 ship between magnetism and light. In Professor 

 Zeeman's words, it shows that light is an electrical 

 phenomenon. Meantime our experiment with the 

 sodium flame demonstrated, obviously enough, a 

 close relation between the activities of molecules or 

 atoms of matter and the origin of light itself. 



LIGHT BEYOND THE SPECTRUM 



A single experiment thus suffices to show curious 

 and interesting relationships between the ultimate 

 particles of matter and those manifestations of energy 

 which we term light, electricity, and magnetism. 

 Meantime it is matter of every-day observation that 

 there is ordinarily the closest relationship between 

 light and that other manifestation of energy termed 

 heat. 



It is no matter for great surprise, then, to be told 

 that the different portions of the spectrum into which 

 a beam of light is spread out show different degrees 

 of temperature when tested by an apparatus of suf- 

 ficient delicacy. It appears, in point of fact, that the 

 dark lines in the spectrum are also areas of relative 

 coolness, and that the spectrum may be charted by 

 moving a sufficiently delicate heat measurer along it. 



106 





