834 
PLEUROPNEUMONIA. 
Referring to the effects of the operation, Dr. Willems says 
that the phenomena of inoculation manifest themselves in 
twelve to thirty days, and sometimes continue for two or 
three months. The disease which is induced, he says, is not 
altogether a local one, as the symptoms exhibited by the 
animal (viz. dulness and loss of appetite) prove. 
The local signs of successful inoculation given by Dr. 
Willems are swelling and hardening of the part operated on 
and the deposition of an excessive quantity of exudative 
matter, of the same kind exactly as that which is found in 
the lungs of an animal affected with pleuropneumonia. In 
his microscopic investigations, Dr. Willems detected minute 
moving molecules in the exudation from the diseased lungs, 
but he failed to detect those bodies in the saliva, urine, and 
blood of sick animals. He also found in the skin of an 
inoculated part a marbled aspect like that of the section of a 
diseased lung. Dr. Willems writes respecting the efficacy of 
the operation as a preventive of pleuropneumonia with the 
enthusiasm of a discoverer; and if his view of the value of 
the remedy were the true one, pleuropneumonia would have 
long ceased to be a scourge to the bovine race. Twenty 
years* experience, however, have not tended to increase the 
confidence of stock-owners in Dr. Willems* discovery, and 
during that time observation has added materially to the 
amount of conflicting evidence which was elicited by the in- 
vestigations of the several scientific commissions appointed 
to inquire respecting the method of inoculation adopted by 
Dr. Willems, immediately upon the publication by him of his 
new method of prevention. 
The Dutch Commission, appointed in 1832, reported in 
reference to the protective effects of inoculation, that 
“ Although the present trials prove in a remarkable degree 
that inoculation possesses the power, at least temporarily, to 
prevent infection, it remains uncertain how far the disposi- 
tion for the disease is completely or only for a longer period 
destroyed.*’ 
The Belgian Commission reported in 1853, in reference to 
inoculation for pleuropneumonia : — 
“ That the inoculation with the liquid extracted from a 
diseased lung is not a certain preventive of pleuropneu- 
monia. 
“That the phenomena of inoculation may be produced 
several times in succession on the same animal whether 
it has previously been affected with pleuropneumonia or 
not. 
“ That the two affections (that produced by inoculation 
