•dvme to the Jn^ispeWJiVe principle of which is, that particular puJastane^ 



bjpothes:!. j^^^^ cwtaiu natural preferences and aversions to positively 



and to negatively electrified metallic surfaces; a^ they 



prove, that. noBUch preferences and aversions are evident, 



while the eub.sti^nces acted on by the eltjctritied surfaces 



rea)»ii3 ip ithetr aatural electrical state. We cannot, indeed* 



by any rpeanB, inf^r from the reijult of ihesse experiments, 



that bouieti do not exist in dift'erent states of electricity ; but 



l^jq must feel saiisfifd, that an acid is not repelled by a 



' pegativejy electrified metallic surface, or an earth or metal 



t^' by a |X)»itively electrified metallic surface;— positions which 



form a very principal part of Mr. Davy's hypothesis, 



Fcculiaritiw -A sjipposition, that dissimilar bodies exist naturally in 



of chemical different eUctrical states, may possibly enable us to account 

 action may be . _ , i- •,• p i • i i t 



accounted for for n?any oi the peculiarities ot chemical action ; but I arn 



by the hypo- inclined to think, fhat these peculiarities are explicable 



equally on wUhout the supposition, aod t]iat the philosophical labours 



other grounds, of BerthoHet have pointed out, with sufficient accuracy, the 



ciccjunjstan.ces, which modify the principle of aUractio«,when 



excited on tb,e i^inute particlee of matter. The question, a^ 



; ^ , p^esepc under consideration, did not, however, originate ia 



^' the phj^iiomena of chemical afi^nity, but w^s rather sugj- 



" gesUd to Mr. Davy, by thie: eltctro-motive property of hqr 



ditis, and tl^e truly vMludbleidi^coveriea which have lately 



beei> eigfe^'ted by me.^us of g^lvani$m. 



lloHies beinr ^^» ^*^'^'' ^^ contact aud subsequent separation of two disy 



indiff rent similg-r bo^iies, they are found to ;be .in di^erent electrical 



afterTepari^" ^tat,f8yip r^spect tQ one another, ijnd to surrounding bodies, 



tionno procf, to what tfiey were ii» before thecpptact, c,an we infer from 



that f hey were j^jjg ^^.^^^ they iliu^t necessarily h^ve exititfd in difieipnt 

 sp beJore. •* y - 



^ectricdl 6tatL-t>, ii* rt-speqt to one aaother, pre\joub|y to th«? 



e^pe/imeu^- Surely not. 'Ihe electric»i«%tates, they now 



j^pssefeSj have evideptly been prod up^d by coiitatt, ov ^phser 



qjueiit beparatioht It may, indeed, be difficult to perceive 



^(B coun^xiop lietween the ^fiect and its cause; but this 



^sa^i^ot^«K^.ra t u-^ i suppO!>ii»g, ttial bodiesiijfiin dift'erent 



elecnicul sta es, w> c cur most dei.cate ini^siunients assure 



, us, ihat they are in sim lar tlectr ca! btaies. W a*- ii, indeed, 



granted to us, that dissimilar bodies have naturally different 



clectfAcal states, we could not, on this principlp, cpp^isiently 



explaim 



