532 On the Discoveri/ of the Atomic Theorij. [May, 



of Philosophy, he would have seen that Berzelius likewise rejects 

 the atomic thcoi y, and substitutes in its place what may be termed 

 the theory of volumes. 



2. The second allegation is likewise true. I have given the 

 credit of the discovery to Mr. Dalton, because 1 thought and still 

 think, that the generalization (which constitutes the discovery) was 

 made by Mr. Dalton. 



S. As to the third allegation I make this answer. The copy of 

 Mr. Higgins's book which has been in my possession since 17^8, is 

 titled on the back Higg'ms on Phlogiston ; and it was so titled when 

 it came into ray possession. The disingenuousness then, of which 

 Mr. Nash complains, must be ascribed not to me, but to the book- 

 seller, or author, or whoever put the title on the back of the book. 

 I merely copied a title ready made out to my hand. After all, the 

 name seems to me not misapplied. The book appears to have 

 been wTitten as a refutation of Kirwan's Treatise on Phlogiston, and 

 I consider it as a very complete one. This probably suggested the 

 title on the back. I beg leave to put Mr. Nash right about the 

 date of the publication of Mr. Higgins's book. It was not pub- 

 lished as he says in 1790, but in 1789. When a man accuses 

 another of inaccuracy and disingenuousness he ought to be very 

 precise in his dates : otherwise he puts it in the power of his anta- 

 gonist to retort the accusation. 



4. The fourth assertion of Mr. Nash has astonished me more 

 than all the rest ; and 1 have been irresistibly led to draw from it 

 the two following inferences : 1. That Mr. Nash is totally unac- 

 quainted with the history of chemistry during the last thirty years. 

 2. That he has never perused JNIr. Higgins's book ; but has merely 

 w'ritten what somebody else has dictated, and written it inaccu- 

 ' rately. 



The composition of metallic oxides was entirely unknown till 

 Lavoisier published his dissertation on the subject in 1778, and it 

 was seven years more before that philosopher could gain a single 

 convert to his opinions. The first attempt at the analysis of metallic 

 oxides was made by Lavoisier in his paper entitled Experiments on 

 the Precipitation of one Metal by another, published I believe in 

 J7S5. When Mr. Higgins wrote in 1789, this was the only set 

 of experiments that had appeared on the subject. Now the fol- 

 lowing table exhibits the results of Lavoisier's experiments. Mr. 

 Higgins gives the same table in page 268 of his book, but in a 

 more mutilated form, and obviously copied at second hand from 

 Kirwan. But I choose to give Mr. Lavoisier's own table without 

 any curtailment, that the case may be stated as strongly in Mr, 

 Nash's favour as possible, 



