S35 On Die Discovery of the Atomic Theory. [MaV^ 



atomic theory. There is not a single attempt at generalization, no 

 allusion to the rate at which the quantity of oxygen increases, no 

 statement of the weight of an atom, or any reference to such a 

 weight. The mere statement of such numbers as Mr. Higgins 

 gives In the preceding passages is not alone sufficient to constitute a 

 man the discoverer of the atomic theory, otherwise the number of 

 competitors would become very considerable. Mr. Chenevix gave 

 two similar examples. He found the oxides of platinum composed of 



100 metal + 7*5 oxygen 

 100 + 15-0 



and the oxides of copper composed of - 



100 metal + 13 oxygen 

 100 + 25 



Yet these facts, which are as striking as any given by Mr. Higgins, 

 did not constitute Mr. Chenevix the discoverer of the atomic theorj'. 

 In the second edition of my System of Chemistry I gave a consi- 

 derable number of similar examples : yet I do not, on that account, 

 lay any claim to the discovery of the atomic theory. The generali- 

 zation, both in ihc case of Mr. Chenevix and myself, as well as in 

 the case of Mr. Higgins, was wanting. And whatever may be the 

 ojiinions of Mr. Nash on the subject, it is tins generalization, for 

 which we are solely indebted to Mr. Dalton, that constitutes the 

 whole merit. Richter had gone still further ; for he had generalized 

 and shown the constancy of the proportions in which acids and 

 bases unite with each other in all cases. He certainly therefore has 

 some claim to at least a share of the merit of the atomic theory. 

 But as I have never had an opportunity of reading his book, I 

 cannot pretend to estimate how far his merit extends. To judge 

 from the papers of his, on the subject, in Crell's Annals, he seems 

 to have been misled by some mystical opinions respecting the figu- 

 rate numbers, and to have had no notion whatever of the atomic 

 theory. 



All that Mr. Higgins then can allege, is, that he was ac- 

 quainted with tlie atomic theory when he published his book, but 

 thought proper to keep it a secret; and would in all probability 

 have kept it a secret for ever, had not the discovery been made by 

 Mr. Dalton. Finding the theory before the public, and finding its 

 importance daily increasing, it would appear that now, after an 

 interval of twenty-five years, he thinks it worth his while to put iu 

 his claim. 



Whetlier Mr. Higgins was actually in possession of this theory 

 twenty-five years ago is a question which we have no means of 

 deciding ; nor do 1 conceive it to be a point of much consequence. 

 We can easily see that if lie knew it, he at least thought proper to 

 keep his own secret. Now it is a law in the republic of letters, 

 and I conceive a very proper one, that if a man makes a discovery, 

 and conceals it, if the same thing be discovered and published by 



