OF PUS IN THE BLOOD. 
47 
ceding observations, it may be proper to advert briefly to the 
nature and use of suppuration, although 1 shall have occasion to 
bring forward the evidence on matters of opinion in a more syste- 
matic form in a future part of these researches. 
Since the microscopic observations of Mr. Hunter, Sir Everard 
Home, and Mr. Bauer, the opinion has often been expressed in 
this country, that the globules of pus are nothing but those of 
blood, modified by the inflammatory process. I believe Sir Ast- 
ley Cooper and the late Dr. Young came long ago to this conclu- 
sion. Finally, on the continent, M. Gendrin, without much re- 
gard to the observations of English pathologists, adopts precisely 
the same theory, supported indeed by a series of very ingenious ex- 
periments, which have been generally considered conclusive on this 
subject. 
I have repeated the experiments of M. Gendrin with great care, 
and although I see no reason to dissent from that part of his con- 
clusion already stated as having been long since advanced in this 
country, I have not been able to observe the phenomena related in 
his work. It seems not improbable that M. Gendrin was influ- 
enced by the erroneous views of M. Milne Edwards as to the 
globular structure of fibrine ; for M. Gendrin states in one place, 
that pus is but a modification of fibrine, although in others he in- 
forms us that it is a transformation of the blood-corpuscles that con- 
stitutes suppuration. By cauterizing the web of a frog’s foot under 
the microscope, or by elevating on the polished blade of a lancet a 
film of the edge of a wound previously made in the part, he assures 
us how easy it is to see the blood- particles gradually transformed 
into those of pus. I regret to say that I have not been able to suc- 
ceed in this observation, because I found, after repeated trials, 
that I could not by any means induce suppuration in batrachian 
reptiles. 
With regard to the conversion of clots of fibrine into pus, some 
experiments render it extremely probable that the matter often 
found in the centre of such clots in the heart and great vessels is 
nothing more than softened fibrine ; and which, although it resem- 
bles pus in some particulars, presents neither the chemical nor the 
microscopical character of that fluid. I have seen nothing like 
pus-globules in the softened fibrinous clots of the heart ; and the 
rounded particles which sometimes occur in softened coagula of 
veins are probably the remains of blood-corpuscles. The conver- 
sion of the latter into those of pus is extremely probable, and it is 
equally probable that this change may take place either in the capil- 
laries or out of them. In the former case, after the stagnation of 
the blood in these vessels which preceded the suppurative process, 
as the clot softened and the pus became mature, it would be carried 
