COAGULATION OF THE BLOOD. 
699 
the ammonia. The surrounding tissues had not been tho- 
roughly protected from its action by the oil, and next morn- 
ing all the parts on which it had acted were the seat of the 
most intense congestion, accompanied with exudation or 
glairy matter into the cellular tissue ; in fact, there were all 
the appearances of the most severe inflammation. Some of 
the exuded matter had trickled down on a board beneath, 
and had there coagulated, showing that genuine exudation of 
lymph had been the result of this post-mortem examination, 
then, I believe for the first time, observed in one of the 
mammalia. I cannot avoid expressing the satisfaction that 
it has given me to find what I had inferred from other cir- 
cumstances, in my investigations on inflammation, now esta- 
blished as a matter of observation. I had found that the 
blood-corpuscles, both red and white, were perfectly free 
from adhesiveness within the vessels of a healthy part, but 
that in an inflamed region they stuck together just as they 
are seen to do between two plates of glass. Having thus 
observed that the corpuscles of the blood comport themselves 
in an inflamed part, in the same manner as in blood drawn 
from the body, 1 inferred that the liquor sanguinis was, in all 
probability, similarly affected, although coagulation is not 
observed in the capillaries, in consequence of the movement 
of the blood ; and I gave the same explanation of the speedy 
coagulation of lymph, and of the formation of clots in 
inflamed vessels, as has been substantiated by independent 
facts this evening. In the paper before alluded to, the fol- 
lowing passage occurs : — 66 The non-adhesiveness of the red 
and white corpuscles, and the fluidity of the blood, seem to- 
be due to one and the same mysterious and wonderful 
agency, — the tissues of a healthy body appearing to extend 
over the blood near them a part of the same influence by 
which they are themselves protected from the action of che- 
mical affinities tending to their decomposition.” We now 
see that when an agent capable of producing inflammation 
acts upon a part in which the blood is at rest, coagulation of 
the blood does really occur in the vessels. 
There is an error of observation into which Dr. Richardson 
has unaccountably fallen, which it appears important to 
correct. In speaking of the coagulation of a portion of blood 
enclosed between two ligatures in the jugular vein of a dog 
or cat, he mentions the formation of a large bubble of air 
within the vessel, a little prior to the occurrence of coagula- 
tion. I have frequently seen the pellucid appearance he 
describes, but find that it is in no way connected with 
coagulation, but is due to the subsidence of the red corpus- 
