404 Dr. Crawford’s Experiments on the Matter 
water. The portion that is infoluble burns with a lambent 
flame, and has all the chara&ers of heavy inflammable air ; 
whereas the foluble part refembles the fluid which is extricated 
from cancerous matter by the vitriolic acid : it has a fetid odour, 
it decompofes nitrated filver, combines with cauftic volatile 
alkali, and poffefies many of the properties of common hepatic 
air. 
There are feveral particulars, however, in which the animal 
and common hepatic air materially cl i it e r from each other. 
Although they are both fetid, yet their odours are not exaftly 
fimilar. When common hepatic air is decompoled by the con- 
centrated nitrous or dephlogifticated marine acid, iulphur is 
feparated ; but when animal hepatic air is decompoled by thefe 
acids, a white flaky matter is difengaged which is evidently an 
animal fubftance, becaufe it becomes black by the addition of 
concentrated vitriolic acid. Sulphur is moreover leparated 
during the combuftion of common hepatic with atmofpherical 
air; but when the air from animal fubftances is burned with 
atmofpherical air, no precipitation of fulphur takes place. 
Indeed, that animal hepatic air does not contain fulphur will be 
apparent from the following experiment. 
Equal parts of pure air and of air extiicated from frefh beef 
by diftillation, were fired by the eledric fhock in a ftrong glafs 
tube over mercury. A little diftilled water was then introduced 
through the mercury into the tube, and was agitated with the 
air which it contained. A portion of this water being filtered, 
and a fmali quantity of muriated barytes being dropped into it, 
the mixture remained perfectly tranfparent. Hence it appears, 
that the air extricated from frefh beef by diftillation does not 
" contain fulphur ; for, if it had contained that fubftance, the 
fulphur, by its combuftion with the pure air, would have been 
I changed 
