£ ! 6 Dr. Crawford’s Experiments on the Matter 
of it which con filled of light inflammable air would require a 
quantity of pure air equal in bulk to the hepatic; and the 
remaining portion, confifting of fulphur, would require a 
quantity equal to i .26 of the hepatic. The entire quantity of 
pure air would therefore be to that of the hepatic as 2.20 to r. 
If the hepatic contained one-twelfth of its weight ot light 
inflammable air, it would require for its duration 1.64 ot Us 
bulk of pure air. But from the foregoing experiments it 
appears, that the quantity of pure air, neceflary to faturate one 
meafure of hepatic air, is only 1.33 meafures. Hence it is 
probable, that this fluid does not confift of fulphur diflolvedm 
light inflammable air. 
If we make allowance for the marine acid which was dtf- 
fufed through the hepatic air, it will be found, that the quan- 
ta of pure air required to faturate it is nearly the fame with 
that which would be required to change an equal weight of 
fulphur into vitriolic acid. Whence it may be inferred, agree- 
ably to the opinion of Mr. Kirwan, that hepatic air is fulphur 
which has acquired an aerial form by the application of heat. 
This conclufion is, I think, confirmed by the following expe- 
Tir Tlittle pure fulphur was introduced into an inverted tube, 
which had been previoufly filled with mercury, and the flame 
of a candle was applied to the extremity of the tube. In a 
fhort time a permanently elaftic fluid was produced, which was 
found to have all the charaffers of hepatic air. It is pr a e, 
however, that fome degree of moifture is neceflary to the fuc- 
cefs of this experiment, becaufe the quantity of hepatic air 
which was thus obtained was not very confidence. 
It has been already (hewn, that an oily matter was produce 
by the union between fixed air, volatile alkali, and amma 
J heoatic 
