chemi^aJ* theory. ,C)| 



"*' tiie-firc particles lodged ia the minium." 1 think I rcmrnj- 

 ber to have seen a commut>iicatit>n from Dr. Priestley in oup of 

 Vhe early numbers of your 8vo. series, wherein he says, that 

 when formerly i a company v/ith'M. Lavoisier at Paris, he in- 

 formed JMr. L, of his ■hiiviT)g obtained a, very pure kind of air 

 from red lead, which \vas what he afterwards named pure or 

 tlcphlogisticated air. 



With regard to oxidat'icn; therefore, and its cause, M. La- lavoisipr cTd 

 voisier did not discover; he only confirmed and extended the bntontvoon- 

 fact. With respect to the theary of combustion, I am sure ^i-m^'^'^lie (act. 

 •11 1 Tt , • • T V n 1 1 The theory i>r 



you will do our -countryman Hooke just)cc. 1 shall only ob- ^.y^j^y^iou >p._ 



serve that I do n'ot think ^ve possess any complete theory of ^'-"iS* ^^^ ^^'--^^-i 

 that process ; fur all that we kno\v is, that the pure part of the 

 uir combines with the body that is burnt, and forms varioiis 

 compounds asccording to the nature and composition of that 

 body : the fShenoMnena of flame as yet are unaccounted for. 

 Nearly the £ame may be said of the claim M. Lavoisicr'makas 

 to the thc&ry of respiration. All the great facts tending to an 

 explanation of tiiat function have been the successive discove- 

 ries of J5oyle, Lower, Black, Priestley, and Crawford; but — supported by 

 nothing in the shape of a satisfactory theory has yet been pro- ]B^y^e'aird 

 diicod. INL Lavoisier's claims, therefore, in this case, as far others, 

 as concerns the facts, are notoriously the discoveries of others : 

 ^nd as to what regards the theory, it is unnecessary to contest 

 with him the right to a thing whicli has no existence. The 

 truth is, Sir, M. Yjusomcv discovered very little, but he improv- 

 ed and (generalized a great deal. No one will question or deny 

 his higlv merits in that point of view, which certainly affords the 

 surest proof of a philosophical genius, inasmuch as the person 

 who constructs the building ranks higher than the mere work- 

 man who prepares the materials. But M. Lavoisier in assist- 

 ing to prepare the materials was too apt to forget his fcllow-la- 

 bourers in the work : and it now appears that ho lays claim to 

 the construction of a building wliich has no.t yet been raised. 

 An impartial and minute observation of the progress and evolu- 

 tion of any science, will convince us, that what may be called 

 " great discoveries" are things of very rare occurrence; and 

 that, perhaps, Newton is the only person whp in the race ol 

 discoveiv has distanced all the rest of mankind, 



N 2 ■Rf/''^* 



