DIVISIBILITY OF MATTER ATOMIC THEORY. 79 



thesis. Chemists are tracing and following them in 

 their most secret operations ; and the latter method 

 has lately obtained a signal success in producing or- 

 ganic compounds from those simple elements the in- 

 cipient combinations of which had heretofore been 

 wholly hidden from us. It is hard to say how far this 

 success may hereafter be carried, but it is certain that 

 the halting-place has not yet been reached. We are 

 still ignorant and here there is no obvious path to 

 discovery of the actual intimate structure of mole- 

 cules. The proportion of number and weight of the 

 atoms comprising them we can tell, but not the man- 

 ner in which they are built up into those definite 

 forms, so numerous to our knowledge, in theory next 

 to innumerable. We cannot penetrate into the atomic 

 attractions and repulsions which govern these pheno- 

 mena, or prove the exact relation of such atomic pro- 

 perties to the great natural forces in constant action 

 around us. We use the general term polarity, and 

 Dr. Prout and others have sought to give it a more 

 specific application to atomic theory ; but all such 

 views, however plausible, are still without proof, nor 

 in any case do they yet meet all the conditions of the 

 question. 



In addition to those already cited I might name 

 many other problems in science which can only be 

 approached through the atomic theory. Such are the 

 phenomena of catalysis the greater energy of certain 

 elements, as oxygen and hydrogen, at the moment of 

 their evolution from compounds the questions regard- 

 ing ozone and other allotropic elements the effects of 



