4S ON SOME CliEMfCAt AGEKCllSS OF ELECTRICITY. 



General pjin. \ 1]( r rubbed or struck against newlv polished lead, always 

 ctplesof the ' . . __ _,,.., , J ' ,, f ' , J 



chemical became positive. Mr. W like perhaps was misled by using 



changes pro- tarnished lead : sulphur, I find, rubbed against litharge, or 

 iricity. ^ a( ^ ^ ie surface of which has been long exposed to air, be«» 



comes negative ; and this exception being removed, all the 

 , facts on the subject are confirmations of the general princi- 



ple*. 



On the gpneral principle, oxigen and hidrogen ought to 

 possess, with regard to the metals respectively, the negative 

 and positive energy. This I have not been able to prove by 

 direct experiments of contact; but the idea is confirmed by 

 the agency of their compounds ; thus I have found, that so- 

 lution of sulphuretted hidrogen in water acts in the electri- 

 cal apparatus composed of single pistes and different strata 

 of fluids, in the same manner as alkaline solutions; and that 

 solution of oxl muriatic acid is more powerful in similar ar* 

 rangements than solutions of muriatic acid of a higher de- 

 gree of concentration ; and- in both these cases, it is impos- 

 sible to conceive the combined hidrogen and oxigen inactive. 

 The inference likewise is fully warranted by the case of the 

 solutions of alkaline hidroguretted sulphurets, which, con- 

 sisting principally of alkali and sulphur together in union 

 with water, exhibit the positive energy with regard to the 

 metals in a very high degree. Tn the series of experiments 

 on Voltaic arrangements constructed with single plates 

 above-mentioned, I found the solutions of hidroguretted sul- 

 phurets in general much more active than alkaline solu- 

 tions, and particularly active with copper, silver, and lead. 

 And in an experiment that I made on a combination of cop- 

 per, iron, and hidroguretted sulphuret of potash, in 1802, 

 I found that the positive energy of the hidroguretted sul- 



* Concentrated solution of phosphoric acid, I find, is decomposed by 

 Voltaic electricity : the phosphorus combines with the negatively electri- 

 fied metal, and forms a phosphuret ; at least this happened in the two 

 cases that I tried with platina and copper. From all analogy it may be 

 inferred, that the electrical energy of this inflammable substance with 

 regard to metals is the same as that of sulphur. I tried some experi- 

 ments of contact upon it, but without success. Its slow combustion in 

 the atmosphere it is most likely was the cause of the failure: but even 

 in gasses not containing free or louse' y combined oxigen, its evaporation 

 would probably interfere. 



phuret 



