[ 38 1 ] 
blood between the ligatures is coagulated. I have 
indeed opened fuch a vein at the end of three days, 
when I found a thin, white coagulum , which was a 
mere film; the Jerum and red particles having difap- 
peared. But the whole is undoubtedly congealed long 
before this period. The manner in which the blood 
coagulates, when at reft in the body, has appeared 
to me curious, and therefore I have taken the more 
pains to difcover how it happens, efpecially as it 
may aftift us in judging whether or no it coagu- 
lates in the heart, l’o as to form thofe fubftances 
called polypi. The abovementioned times will, I 
believe, be found to be thole at which the blood 
congeals in the veins of healthy dogs : and as I 
have found, by experiments, that the blood of a 
dog and of the human fubjedt in health jellies out 
of the body nearly in the fame time, that is, it 
begins in three or four minutes, and is completed in 
feven or eight ; I fhould therefore conclude that the 
blood coagulates nearly at the fame period in the 
veins of the human body. But it may be necelfary 
to add here, that from experiments which I have 
made, I have reafon to believe that the time at which 
the blood coagulates, is different in different con- 
ftitutions, and in different difeafes. For though the 
blood of a perfon in health is completely coagulated 
in feven minutes after it is taken out of the veins, yet 
in fome difeafes, I have found the blood fifteen or 
twenty minutes, nay even an hour and an half, be- 
fore it was completely jellied. 
As we fee in the above related experiments, that 
the blood coagulates in the body when buffered to reft 
for a little time, is it not probable that tis to this 
caufe 
