C 3+7 ] 
like globules of quickfilver, as happened to the 
urinary bladder in the experiments at Shiffnal ; 
which, in both cafes, we afcribed to fome por~ 
tion of cellular membrane adhering to the bladders, 
into the cells of which, at the time of cutting them 
out, fome air had infinuated itfelf. 
In thel'e experiments the water, in which the ani- 
mal parts were immerfed, was warmed to about an 
hundred degrees of Fahrenheit’s fcale, left a greater 
degree of heat in the water might have railed an 
elalfic vapour from thefe fluids, which did not na- 
turally exift in the living animal ; and all the parts 
were well cleared from the cellular membrane and 
fat i as it was imagined the atmofpheric air might 
intrude itfelf into the cellular* membrane, as is feen 
in tearing off the fkins of animals recently killed, and 
which did indeed aifappoint two of the above experi- 
ments, as was manireft from the filvery globules, 
which appeared upon the furfaces of the bladders. 
From the fadts eftablifhed by thefe experiments, 
we may draw the following conclufions. 
I . That fo great a change is produced in the blood, 
by its receiving, in its paflage from the arm of the 
patient to the bafon, a great admixture of atmo- 
fpheric air, that the experiments afterwards made 
on its fenfible or chemical properties are rendered 
very uncertain and erroneous ; ft nee the fluid colour 
of the blood, its property of coagulation, and per- 
haps of putrefaction, may depend on this afcititious 
admixture of atmofpheric air : and, at the fame 
time, we fee why fo much lefs froth is produced 
in the operation of cupping, than from blood placed 
in the exhaufted receiver of an air-pump; though 
Y y 2 perhaps 
