Some Account of Richard Ktrtvan, Efq. 353 



about nine lines in diameter, and clofed by mercury, a mix- 

 ture of four parts in volume of carbonic acid gas, and three 

 parts of hydrogen gas. The fpace occupied by the two aeri- 

 form fluids united formed a long column of feven inches, fo 

 that each part in volume of the glafs correfponded to one 

 inch in length of the column. I caufed the eleftric fpark to 

 circulate by iron conduftors. The condenfation of the gas, 

 which at firft took place very rapidly, became always flower; 

 after twelve hours eledlrifation, its progrefs was almofl: infen- 

 fible. The very fine drops of water, formed during the ope- 

 ration in the upper part of the tube, difturbed its tranfpa- 

 rency. The column of aeriform fluid was reduced to four 

 inches. It then experienced in its length a diminution 

 equal to three inches. T then introduced into it potafh, which, 

 could abforb only one inch of carbonic acid gas. The three 

 remaining inches were carbonous gas almofl: pure. I burned 

 by means of the eleftric fpark, loo parts of it with oxygen 

 gas, and they left for refiduum 64 parts of carbonic acid gas. 

 It is feen, then, that three inches of carbonic acid gas were 

 decompofed, and pafled to the fliate of carbonous gas, by 

 combining a part of their oxygen with the hydrogen gas in- 

 troduced. It is feen alfo that the latter, by lofing the 

 elaftic flate to form part of the water refulting from this com- 

 bination, produced the condenfation obferved in the volume 

 of the two gafes. 



It is to be remarked, that the mercury and condudors in 

 this experiment were not confiderably oxidated. 



It has long been obferved, that hydrogen gas, confined by 

 water in contaft with atmofpheric air, decreafes very flowly 

 in volume, and then burns with a flame lefs vivid. It has 

 been fuppofed that this gas filters through the water in the 

 atmofphere; but there isliothing to fupport this explanation. 

 In my opinion, it is more probable that the carbonic acid 

 gas of the atmofphere filters alone througli the water, ac-» 

 cording as it is decompofed by the hydrogen gas, which de- 

 creafes in the ratio of this decompofilion. 



LIX. Some Account of Richard Kirwan, Efq. LL. D. 

 F.'ti.S. and P. R.I. A. 



L HLS orentleman, who has diftinguiflied himfelf fo much 

 by liis plulofophical and geological labours, was bred to the 

 law, and cxercifed his profellion as a barrifler, lili iiifinii 

 health, and the death of his elder bryihcr, a member of the 

 IriOi parliament, occafioned him to become an experimental 

 Vol. XIV. No. 56. Z jn4uir«r 



