454 
ON THE CAUSES OF COAGULATION OF THE BLOOD IN 
DISEASES OF THE BLOOD-YESSELS. 
By Joseph Lister, Esq., E.R.C.S. Eng. and Edin. 
Mr. Lister read a paper before the Medical and Chi- 
rurgical Society of Edinburgh, in March last, on the above 
subject, coupling it with a case of spontaneous gangrene 
from arteritis in the lower limbs of a child. Having described 
the case, he goes on to say — 
“ But my chief reason for bringing the case now before 
the Society is, because it appears a distinct example of in- 
flammation of the coats of a vessel determining coagulation 
of the blood within it, without the exudation of lymph into 
its interior. Not that there is any novelty connected with 
such an occurrence, but because this effect of arteritis and 
phlebitis, long recognised by all sound pathologists, appears 
to be of peculiar interest at the present juncture, in con- 
nexion with the recent publication of the last Astley Cooper 
Prize Essay, in which Dr. Richardson of London propounds 
the theory, that the coagulation of the blood is due to the 
escape of a minute quantity of ammonia, which he believes 
holds the fibrine in solution. I propose, therefore, on the 
present occasion, to consider how far this new theory accounts 
for the phenomenon of coagulation in inflammation and other 
diseases of the blood-vessels. 
“ So short a time having elapsed since the publication of 
the volume alluded to, it may be well to mention, as briefly 
as possible, the main facts by which the arguments of the 
author are supported. And first I may relate the startling 
observation made by Dr. Richardson, that if a current of air 
is passed through two successive portions of freshly drawn 
blood, contained in two Wolfe's bottles, while that in the 
first bottle, as might have been expected, has its coagulation 
accelerated, that in the second bottle is prevented from coagu- 
lating for several minutes after the time at which it would 
have solidified, had it been left in the vessel without inter- 
ference. In other words, the air has had its properties so 
modified in passing through the first mass of blood, that it 
afterwards retards instead of promoting coagulation ; whence 
Dr. Richardson infers, that it has obtained in its passage 
some volatile solvent of the fibrine. Secondly, Dr. Richardson 
has discovered that a very minute quantity of ammonia added 
to freshly drawn blood keeps it fluid for an indefinite period 
in a stoppered bottle, but that if exposed to air it coagulates 
as usual, though at a later period, in proportion to the 
amount of ammonia employed. He also finds that, by careful 
