118 Cn some Chemical Agencies of 'Electricity. 



On the general principle oxygen and hydrogen ought to 

 possess, with regard to the metals respcctivelv, the negative 

 and positive eneriiy. This I have not hcea able to prove by 

 direct experiments of ctmtact ; but the idea is confirmed by 

 the agency of their compcnnds : thus I have found thai so- 

 lution of sulphuretted hydrogen in water acts in the elec- 

 trical apparatus, composed of single plates and difitrent 

 strata of fluids, in the same manner as alkaline solutions; 

 and that solution of oxymuriatic acid is more powerful in 

 similar arrangements than solutions of muriatic acid of a 

 higher degree of concentration ; and in both these cases 

 it is impossible to conceive the combined hydrogen and 

 oxvgen inactive. The inference, likewise, is fully warranttd 

 by the case of the solutions of alkaline hvdrogurct;ed sul- 

 phuretSj which consisting principally of alkali and s .Iphur 

 together in union with water, exhibit the positive energy 

 with regard U> the metals in a very high degree. In the 

 series of experiments on Voltaic arrangements, constructed 

 with single plates above mentioned, I found tlje solutions of 

 hvdrogurerted sulphurets m general much more active than 

 alkahne solutions, and particularly active with copper, silver, 

 and lead. And in an experiment that 1 made on a combina- 

 tion of copper, iron, and h\drogurctted sulphurets of pot» 

 ash, in 1802, I found that the positive energy of the hvdro- 

 gurettcd sulphurets with regard to the copper was sutTicient 

 to overpower that of the ron ; so that the electricity did not 

 circulate trorn the copper to the iron, and from the iron to 

 the fluid, as in common case?, but from the copper to the 

 hydrogure;ted sulphuret, and from tlie hydroguretted sul- 

 phuret to the iron. 



All these deta Is arTord the strongest coufirnnation of the 

 principle. It mpy be considered almost as a mere arranire- 



mctal, and forrr.s a phosphuret; at least this happened in the two ca?cs that I 

 tried with platfha a..d copper From all analogy it may be inferred th.it the 

 electrical ener-^y ot this iaflimmnble s'lbstaiice wiili rej^ard to ineials h the 

 Jarre au that of sulphur. I tried some c«peri.;;cnis < f contact upon it, but 

 without success. Its slow combustion in the atmoEphtre, it is most likelv, 

 was the . ause of tlie failure; but even in ^ases not containing free or loosely 

 combined oxygen, its evaporation -.would probably imerftre. 



mcnt 



