EDITORIAL OBSERVATIONS. 
577 
<c Another statement that has been made with reference to 
the mode of action of inoculation is equally unfounded, 
viz. that although inoculation never produces actual pleuro¬ 
pneumonia, yet, that it gives rise, at the place where the 
morbid material is introduced beneath the skin, to a local 
disease which is of the same kind as the real disease of 
the lungs, and that consequently the effect of the inocu¬ 
lation is to produce a sort of pleuro-pneumonia of the skin !’ 
That is to say, in reality, that the animals have a modified 
form of pleuro-pneumonia in their tails! Dr. Burdon 
Sanderson goes on to show that f the only way in which it 
would be possible to prove that any diseased material derived 
from the skin of the inoculated animal was pleuro-pneumonic 
would be by showing experimentally that when introduced 
into another animal it produced pleuro-pneumonia. If this 
4 
proof were given w’e should have a right to conclude from 
analogy with similar cases, that in all probability immunity 
would be conferred on the infected animal; but in the 
absence of such proof, the only way in which the protec¬ 
tive power of inoculation can be settled for practical pur- 
purposes, is by observing whether inoculated animals can 
get pleuro -pneumonia by exposure/ Precisely so ; and the 
question naturally raised is, for how long Mr. Rutherford's 
inoculated animals can be proved to have resisted con¬ 
tagion.” 
This is perfectly fair criticism, and we may say at once that 
it includes the common sense, as well as the scientific aspect 
of the position. We do not for a moment question Mr. 
Rutherford’s skill as an operator, but there cannot be any¬ 
thing in his method which is so decidedly different from that 
adopted by Mr. Priestman for the last thirty years, and by 
others here and abroad, as to justify the claim of absolute 
infallibility which is urged in its favour. Inoculated cattle 
do frequently become affected after inoculation, and in some 
of the countries where inoculation is most practised the 
disease is most prevalent; for example, England, Belgium, 
Germany, Australia. As far back as 1853, as veterinary 
adviser of the Royal Agricultural Society, we were com¬ 
missioned to investigate the subject in Belgium, and we 
lii. 41 
