242 



Three at pre- 

 sent distill- 

 guished 



I. Carbonic 

 oxide. 



II. Carbureted 

 hydrogen. 



III. defiant 

 gas. 



Opinion of 

 chr-n-iisk ^s 10 

 their naLUie. 



INFLAMMABLE GAS. 



cesses of the operator, and the number of substances from 

 which I hey are obtained. That we are already acquainted 

 with all the inflammable gases from vegetables, which it is pos- 

 sible to form, is an opinion which but ill accords with the pre- 

 sent imperfect state of chemical knowledge. But it is to be 

 hoped, for the future progress of the science, that the opposite 

 doctrine is equally unfouri^ded; for, were the number of such 

 gases indefinite, the examination of them would be not only a 

 disgu^ing and hopeless task, but altogether useless and nu- 

 gatory. 



Three distinct inflammable gases from vegetables, are at 

 present known, and characterized with considerable precision. 

 These are, 



I. Curb mic Oxide, first accurately examined and analyzed by 

 Mr. Cruikshanks, and lately shewn by Mr. William Henry, to be 

 not unfrequently produced during the distillation of vegetable 

 substances. It is characterized by a specific gravity, nearly 

 equal to that of common air, by the blue flame with which it 

 burns, the .mall quantity of oxygen which it consumes, and the 

 great proportion of carbonic acid which it forms. 



II. Carbureted Uylrogen, a gas which ri-ies spontaneously 

 from mar-hes in hot weather. Its specific gravity is exactly 

 6-lOths of (hat of common air: it burns with a white flame, 

 consumes "twiqe its bulk of oxygen gas, and forms exactly its 

 own bulk of carbonic acid. 



III. Oltfiani Gas, or Supsrcarbureted TJydrogsn, a gas which 

 is proctired by distilling a mixture of four parts sulphuric acid 

 and one part alcohol, an 1 which Mr. William Henry has shown 

 to be e\'olved in great quantities during the combustion of pit- 

 coal. It \i characterized by the property which it has of 

 losing its ga^^eou!^ form, and assuming that of an oil, when 

 mixed wi*h three times its bulk of oxymuriatic acid gas. Its 

 spei;ific giavlty is 9-lOths of that of common air. It burns 

 with a ye.iowish white flame, like oils, and emits more light 

 than an^ other gas. It con-ume^ thiee times its bulk of oxy- 

 gen gas, anci {('ica'^ twice, its bulk oi carbonic acid. 



Tht; iirst of these ga^es !> ( onsidered at present, by the 

 grtaiei number, of che^iiist , as a compound of carbon and 

 o>iy;r,eii, the tvvo last as compound ol ca-bon and hydrogen, 

 ditffc.ing from each other in the proportion of carbon ; the first 



containing 



