CELESTIAL DISSOCIATION. 205 



vanadium and strontium. To these supposably broken- 

 down metals the prefix proto is applied. By pro to-iron, 

 proto-copper and proto-nickel, for example, is meant the 

 constituents of iron, copper and nickel as they exist in the 

 sun or hottest stars. A very important proto-element is 

 proto-hydrogen, discovered some time ago by Professor 

 Pickering of Harvard University, in the star named zeta- 

 Puppis in the constellation Argo. The spectral lines rep- 

 resenting this substance Pickering at first supposed to 

 signify a new element; but he was able to show, later, 

 that they belonged to a new series of hydrogen lines con- 

 stituting a form of hydrogen unknown on earth. Subse- 

 quently, this same proto-hydrogen was discovered in the 

 stars 29 Canis Major and gamma- Argus. It is interesting 

 to note that this broken-down, or proto-hydrogen, is con- 

 ' fined to the very hottest stars known. 



If we accept the dissociation hypothesis, these curious 

 proto-spectra are naturally, simply, and sufficiently ex- 

 plained. If we reject it, we shall look in vain for any other 

 present-day explanation which will co-ordinate and har- 

 monize the observed results. 



In our studies of the periodic law and radio-activity, we 

 found reason to believe that the elements were not by any 

 means the simple bodies formerly believed in, but that the 

 atoms of these elements were highly complex and were built 

 up of particles finer still. We saw reason to believe that 

 in the solar and stellar furnaces, if anywhere, we should find 

 these sub-elemental forms of matter existing in a stable 

 form, and that we do find a series of remarkable phenomena 

 which can be explained only on the supposition that we 

 previously had every reasonable reason to believe, surely 

 strengthens and rivets tight the whole hypothesis of the res- 

 olution of the atom. 



