of Cancer , and on Animal Hepatic Air . 425 
increafing the morbid adlion of the veffels, would be produdtive 
of falutary effects. The nitrous acid does not deftroy the fetor 
of hepatic air, unlefs it be highly concentrated ; and in this 
ftate it is well known that it fpeedily corrodes animal fub- 
ftances. But the fetor of hepatic air quickly difappears when 
it is mixed with the dephlogiflicated marine acid, even though 
the latter be fo much diluted with water as to render it a very 
mild application. 1 have found that this acid, diluted with 
thrice its weight of water, gives but little pain when it is 
applied to ulcers that are not very irritable; and in feveral 
cafes of cancer it appeared to corredt the fetor, and to produce 
a thicker and more healthy pus. It is proper, however, to 
remark, that other cafes occurred in which it did not feem to 
be attended with the fame falutary effedts. Indeed, fome can- 
cerous ulcers are fo extremely irritable, that applications which 
are at all of a ftimulating nature cannot be ventured upon with 
fafety. And hence if the obfervations, which I have made on 
the efficacy of this acid as an external application, fhould be 
confirmed by future experience, it miift be left to the judge- 
ment of the furgeon to determine both the degree of its dilution, 
and the cafes in which it may be employed with advantage. 
The dephlogifticated marine acid, as is generally known, 
has the power of deftroying the colour, the fmell, and per- 
haps the tafte, of the greater part of animal and vegetable 
fubftances. We have feen that it corredls the fetor of putrid 
fleffi. And I have found, that, when it is poured in fufficient 
quantity upon hemlock and opium, thefe narcotics fpeedily 
lofe their fenfible qualities. As it appears, therefore, to poffefs 
the power of corredting the vegetable, and probably many of 
the animal poifons, it feemed not unlikely, that it might be 
ufeful as an internal medicine. Conceiving that its exhibition 
Vo l. LXXX. K k k would 
