8 Clarke, The Atomic Theory. 



conception that all combination must take place in fixed 

 proportions was not new, and, indeed, despite the objections 

 of Berthollet, was generally assumed ; but the atomic 

 theory gave a reason for the law, and made it intelligible. 

 The idea of multiple proportions had also occurred, 

 although incompletely, to others ; but the determination 

 of atomic weights was altogether original and novel. The 

 new atomic theory, which figured chemical union as a 

 juxtaposition of atoms, coordinated all of these relations, 

 and gave to chemistry, for the first time, an absolutely 

 general quantitative basis. The tables of Richter and 

 Fischer, who preceded Dalton, dealt only with special cases 

 of combination, but they established regularities which 

 rendered easier the acceptance of the new and broader 

 teachings. The earlier atomic speculations were all purely 

 qualitative, and incapable of exact application to specific 

 problems ; Dalton created a working tool of extraordinary 

 power and usefulness. Between the atom of Lucretius 

 and the Daltonian atom the kinship is very remote. 



Dalton was not a learned man, in the sense of mere 

 erudition, but perhaps his limitations did him no harm. 

 Too much learning is sometimes in the way, and clogs the 

 flight of that imagination by which the greatest discoveries 

 are made. The man who could not see the forest because 

 of the trees was a good type of that scholarship 

 which never rises above petty details. It may compile 

 encyclopaedias, but it caiuiot generalise. In some ways, 

 doubtless, Dalton was narrow, and he failed to recognise 

 the improvements which other men soon introduced into 

 his system. The chemical symbols which he proposed 

 were soon supplanted by the better formulae invented 

 by Berzelius, and his views upon the densities of gases 

 were set aside by the more exact work of Gay Lussac, 

 which Dalton never fully appreciated. As an experi- 



