Additional Obfervat'wns on Hydrocarlonates. 203 



gas occupied only ,43 parts of a meafure, or a diminuttpji of 2.57 meafares had taken 

 place. This rcfiduary gas being agitated with lime water, .09 parts more were abforbed, 

 evidently carbonic acid gas. The wafhed refiduum was inflammable, and burned with a 

 blue lambent flame, exaftly fimilar to the gafeous oxides, but very diiFcrent from that of 

 the original hydrocarbonate. 



This experiment was repeated with nearly the fame refults. 



In this inftancc, however, the gas had been recently obtained from camphor, which I 

 have always found made a confiderable difference in the proportions of the produfts.* On 

 the addition of the oxigenated muriatic acid gas to the hydrocarbonate, a diminution of no 

 lefs than three-fourths of a meafure immediately took place, and after (landing for twenty- 

 four hours, the water, on withdrawing the ftopper, rofe fo high, that the remaining gas 

 occupied the fpace of not more than .54 parts of a meafure ; hence the whole diminution 

 muft have been 2.46 meafures. This refiduary gas contained one-fifth of its bulk of car- 

 bonic acid, the remainder being inflammable. Two fmall meafures of this inflammable 

 gas, fired with two meafures of oxigen in a jar, over mercury, were reduced to 2.^ 

 meafures; of this 1.7 were carbonic acid, and the remaining .8 or .9 oxigen gas j iotix 

 required very nearly two meafures of nitrous gas to faturate them. 



Hence we perceive that two meafures of this gas, combined with about one of oxigen, 

 produced no lefs than 1.7 meafures of carbonic acid ; a circumftance which proves it"to 

 have been the gafeous oxide of carbon. 



Being determined to vary the experiments as much as poflible, to prevent any miftakc or 

 overfight ; I introduced into a bottle, filled with and inverted over mercury, two meafures 

 of hydrocarbonate from jether, and immediately after four meafures of the oxigenated 

 muriatic acid gas. Thefe completely filled the bottle, which was flopped to prevent the 

 acid gas from afting upon the mercury ; its neck was then plunged under mercury, and 

 kept down by a weight placed upon it. 



After (landing for twenty-four hours, the ftopper was withdrawn under mercury, which 

 inftantly rofe and filled two-thirds of the bottle ; there was a little moifture depofited on its 

 fides, which probably abforbed the whole of the common muriatic acid gas produced. 

 Lime water in excefs being now added, one-third was found to be carbonic acid, and the 

 remainder inflammable. 



* It might be fuppofed that this difference arifes from the abforption of carbonic acid gas ; but this is by 

 no means the cafe, for the proportion of this gas in the hydrocarbonates from aether, or camphor, is exceed- 

 ingly fmall, never exceeding one-tenth, and frequently much lefs. Befides, I found, fiom direft experi- 

 ment, that the unwaflied hydrocarbonate required more oxigen to faturate it, than the waflied, the reverfe of 

 virhich (hould have been the cafe, had the difference depended upon carbonic acid. This variation in the 

 refults may be thus itated :-— One meafure of unwafhed hydrocaibi-nate requires 1.9 of oxigen to fatu.ate it, 

 the produfls being water, and 1.4 meafures of carbonic acid. But one meafure of the waflied gas requires 

 only 1.65 meafures of oxigen, and produces about 1.15 meafures of carbonic acid with water. 



It appears to me, therefore, that fomething like a vapour diffuled through the gas, which may be feparated 

 by wafhing, or depofited on Handing, muft be the caule of this change in their propeities. 



Dd2 ' Two 



