Dr. Pearson on expectorated Matter. 331 
however, satisfy myself, that the small quantity of liquid 
decanted from off this sediment contained a kind of vegetable 
acid for the first time apprehended in the fluids of animals ; 
because, first, the quantity of product I possessed was so di- 
minished by many experiments, that I was unable to make 
what I considered to be decisive trials. Secondly, because in 
subsequent processes I failed in producing the same apple- 
smelling liquid. Hence I considered that the supposed acid, 
which had some of the properties of the malic, only occurred 
occasionally, or that I had been deceived, and that I had pro- 
cured nothing more than a little of the acid employed for the 
decomposition, disguised by mixture with the subject of the 
experiments. The fawn-coloured precipitate was, no doubt, 
chiefly muriate of lead. Still the experiments fully demon- 
strate the presence of potash neutralized, either by an acid 
destructiole by fire and dissoluble in alcohol, but hitherto not 
disunited from animal oxide, or that an oxide of animal matter 
alone neutralizes the potash, as will be manifested by the 
evidence of experiments to be related. 
(<?). Forty-five grains of the residue (r) which had been 
dissolved in alcohol, being burned in a platina crucible, 
yielded chiefly potash, and half its quantity of muriate of 
soda. 
(/). Twenty-five grains of the residue (c) were boiled 
with successive portions of nitric acid, till the oxide of animal 
matter was decompounded and carried off in the state of 
gases ; and then deflagration took place, leaving subcarbonate 
of potash with muriate of soda and charcoal. 
According to a computation, the 140 grains of resin-like 
extract (c, d) consisted of twenty-eight grains of potash, and 
