On some Chemical Agencies of Electricity. 1 1 3 



These facts seem fully to invalidate the conjectures of 



M. Riltcr, and some other philosophers, with regard to the 



elementary nature of water, and perfectly to confirm the 



great discovery of Mr. Cavendish. 



M. Rittcr conceived tliat he had procur-.^d oxygen from 

 water without hydrogen, hy making sulphuric acid the me- 

 tlium of coniniunicalion at the negative surface; but in this 

 case sulphur is deposited, and the oxygen from the acid and 

 the hydrogen from the water are respectively repelled, and 

 a new conilii nation produced. 



I have attempted some of the experiments of decomposi- 

 tion and transfer by means of common electricity, making 

 use of a powerful ck:clrical machine of Mr. Nairne's con- 

 struction, belonging to the Royal Institution, of which the 

 cylinder is 15 inches in diameter, and two feet long. 



Wuh the same apparatus as that employed for decompo- 

 sitions by the Voltaic battery, no perceptible effect was pro- 

 duced bv passing a strong current of electricity silently for 

 four hours through sclulion of sulphate of potash. 



But bv eit)ploymg fine platina points of 1 70th of an inch 

 in diameter, cemented in glass tubes in the manner con- 

 trived I)y Dr. Wollaston*, and bringing them near each 

 other, in vessels containing from three to four grains of the 

 solution, and connected by moist asbestus, potash ap]ieared 

 in less than two hours round the negatively electrified point, 

 and sulphuric acid round the positive point. 



In a similar experiment sulphuric acid was transferred 



through moist asbestus into uater; so that tliere can be no 



doubt that the principle of action is the siuiie in counnon 



and the Voltaic electricity f- 



VII. On 



* Phil. Trans, vol. xci. p. 427. 



t This bad licen phown, wltli regard to the decomposition of water, by 

 Dr. Wollaston's important restarchcs. By carefully avoiding sparks, 1 have 

 been able to obtain the two consiitiients in a aepar.ite stale. In :in experiment 

 in which a fine platina point ccmcnlcd in glass, and connected by a single wire 

 with the poiiitivc conduotur of this m.irliine, was plunged in distilled w.iter in 

 an insulated s'atc, and the cicctiicity disbipnicd into the atmosphere by mean* 

 of moistened filaments of cotton, oxygen gas mixed with a little nitrogeh ga» 

 ■was produced ; and when the same apparatus was :ipplltd to the negative 

 conductor hydrogen gas was evolved, and a minute puriion of oxygen and 



Vul. 29 . No. 1 iO. Juiu 1 807. H aitroifen 



