162 INOCULATION FOR PLEURO-PNEUMONIA IN CATTLE. 
their value in an investigation of this description. It would 
appear that the malady was likely this year also to increase 
towards the autumn, as three or four cases occurred just as I 
was about to leave Hasselt ; and it is therefore probable that 
inoculation may have a severe test even in that place. These 
cases happened to ^oft-inoculated animals, and in sheds where 
some had been inoculated. Thus M. Vanstraelen keeps 
twenty-four, of which eight only were inoculated; a non- 
inoculated cow was taken ill on September 2d, and died on 
the 10th, being allowed to remain with all the others three or 
four days before removal. M. Rosseau keeps twenty-seven, 
and has not had any inoculated, notwithstanding which his 
cattle were exempt from the disease for seven months , and up 
to the last week in August, when one was taken ill and sold ; 
another was attacked within a few days, and was evidently 
fast sinking when I saw her. These animals also had free 
communication with the others. Such instances as these are 
sufficient to establish the points just referred to; and it be- 
comes therefore unnecessary to multiply cases of the same 
description. 
The statements given by different persons are very contra- 
dictory, as will appear from the sequel of this report. Even 
on the subject of protection by inoculation Dr. Willems 
does not allow a single failure , while others assert that several 
such instances have occurred. With regard to the local indica- 
tions of a successful inoculation, although I witnessed many 
operations performed by Dr. Willems, and inspected the 
parts at different intervals afterwards, I saw none which, to 
me, were satisfactory. Unhealthy inflammation, ulceration, 
sloughing, and gangrene, were far too frequently the results 
of the operation. The punctures are made very deep, with a 
double-edged scalpel, which is thrust through the skin, and 
moved from side to side to allow the two or three drops of 
fluid used for the inoculation to penetrate to the bottom of the 
wound. Surgical and scientific principles certainly did not 
rule in these operations. What the effects may be of a dif- 
ferent mode of procedure I am unable at present to say, but to 
establish the value of inoculation further experiments should be 
adopted. Another point of the first consequence is suscep- 
tibility to a re-inoculation. It is said by the advocates of the 
system, that such susceptibility is entirely destroyed by the 
first inoculation. Among other animals which I was shown by 
Dr. Willems were two cows belonging to his father that had 
been operated upon fifteen months, and which, he assured 
me, he had rtf-inoculated three or four times, and in each in- 
stance without success. Capability of transmitting “the 
virus” from animal to animal, by what is technically called 
