26G THE CHEMISTRY OF THE SUN. [CHAP. 



might go further and say that all the processes of development 

 observed in different regions of thought, have such a oneness 

 about them that to my mind one of the best mental images we 

 can get of the conditions which determine the lines picked 

 out for special prominence in solar spots and solar flames, is to 

 consider the molecular groupings that produce them as re- 

 sembling the roots of the present European languages which our 

 ancestors brought from the cradle of the race in Asia. 



Now comes the second question, to which reference has been 

 made. What is the opinion of those who have given the great- 

 est attention to chemical philosophy ? I do not mean to chem- 

 istry, I mean to chemical philosophy. I have already referred 

 to Brodie's clear statement, but we can anticipate his time by a 

 reference to Dalton. He says, " We do not know that any one 

 of the bodies denominated elementary is absolutely indecom- 

 posable." Graham also wrote, " It is conceivable that the various 

 kinds of matter now recognised in different elementary sub- 

 stances may possess one and the same element or atomic 

 molecule existing in different conditions of movability. The 

 essential unity of matter is an hypothesis in harmony with the 

 equal action of gravity upon all bodies." The greatest chemical 

 philosopher now living, M. Dumas, so long ago as 1836 published 

 a series of lectures in which his views were very clearly stated 

 indeed, and any one who reads them will see how convinced he 

 was then of the considerable amount of evidence that had 

 already been accumulated in favour of the non- elementary 

 nature of a great number of substances then classed as elements. 



Then again we can pass to another chemical philosopher, 

 Kopp. In his researches on specific heats he also gives evidence 

 to show that that relationship is not to be depended upon to 

 establish the received view. If, then, the three greatest English 

 chemists of their time we can name, and the most eminent 

 chemical philosophers in France and Germany, give their opinion 



