HISTORY OF THE ATOMIC THEOEY. 219 



the compound formed. For example, a salt, say an oxalate, 

 decomposes a salt of lime, not because the oxalic acid has 

 such a powerful aflSnity for lime, but because the oxalate of 

 lime being insoluble falls, following the physical qualities of 

 the compound ; oxalic acid too decomposes common salt, not 

 from a greater affinity, but because muriatic acid being vola- 

 tile, has a way of escape, whilst oxalic acid has not, and 

 so on. 



These and similar reasonings took up such a large portion 

 of his field of vision, that he denied, as we have seen, definite 

 proportions, and, of course, atomic theories and equivalents 

 could never be received from BerthoUet. He denied definite 

 proportions in the present sense, but, as Berzelius says, 

 allowed them, although within certain limits. This would 

 imply proportions of a rather indefinite kind. In the 

 " Memoires de la Societe d'Arcueil," he even gives laborious 

 analyses tending to fix the proportions of the elements in 

 certain bodies. This was chiefly from the point of view that 

 distinct bodies had determinate and constant composition, 

 which, of course, it would have been too late to deny. 



BerthoUet did, nevertheless, put a drag on the inquiry 

 into the general question of proportion, and from his 

 superior position commanded great influence. It is in this 

 state we find the science, then, when Dalton came to it. 

 It may be said that the state of the science comprehended all 

 that was published, and this is in a larger sense true, and con- 

 stitutes the base of a final opinion of a discoverer's merits; but 

 the state of what seemed to be the well-grounded science, as 

 far as the leading men held it, was rather that of BerthoUet 

 than any others, the leading innovators were obscure, and never 

 indeed became magnates in the scientific world. These latter 

 commanded to all appearance in the capital, whilst the real 

 power was getting prepared in the provinces. 



Berthol let's essays must always stand as the greatest proofs 

 of the reality of Dalton's achievements. Whatever men may 



