[ 375 3 
be particular in giving a detail of their effedts, from 
our not knowing of any ufe this would be in me- 
dicine, becaufe we mull not conclude that their ef- 
fects in the body would be the fame as we fee they 
are out the body. Indeed, thefe experiments, as 
well as many others, were not made fo much with 
a view of any immediate application to medicine, as 
to determine the properties of the blood chemically : 
for, having fet out with a perfualton, that a more par- 
ticular acquaintance with the properties of this fluid 
was neceflary before we could arrive at the knowledge 
of fome of the animal functions, fuch as the manner in 
which the bile and other fecreted fluids are formed, I 
therefore determined to do my utmoft to throw fome 
lignt on this fubjedt. It was with this view that I 
have made fome experiments even on living animals, 
being convinced that fuch experiments could not 
otherwife be made fatisfadlorily. 
When blood is thus kept fluid by neutral fait?, 
it ftill retains its property of being coagulable by heat, 
and by other fubftances as before, air excepted. This 
method of keeping the blood fluid may therefore be 
ufeful, by giving us an opportunity of making fome 
experiments on the blood, which we could not other- 
wife do, from its coagulating fo foon when taken from 
the blood-veffcls. 
This property of one of the neutral falts has been 
long known, amongft thofe who prepare blood for 
food ; for it has long been a pradhce with fuch peo- 
ple, to receive blood into a veflel containing common 
fait, and to agitate it as fall as it falls, by which 
means the coagulation is prevented, and the blood 
remains fo fluid as to pafs through a cloth, without 
3 leaving 
