MEDIATE CONTAGION IN PLEURO-PNEUMONIA. 
65 
to take the entire pleuro-pneumonia work away from the Bureau 
and place it with an independent commission? “And its business 
controlled by a committee, one of whom was Dr. Salmon, the 
head of that Bureau.” Yes, I was a member of a committee of 
five on order of business, but I do not see any particular reason 
for surprise in that fact, as I was a regularly appointed delegate. 
“ Unfortunately,” he goes on, “ the facts that I had gathered 
did not agree with the theories of Dr. Salmon, and my paper and 
the accompanying correspondence met an ignominious fate in 
this committee of censors, there suffering strangulation.” The 
doctor is not correct in this statement; his paper was simply 
declined as were all others that were not prepared by invitation 
of the executive committee. The convention had certain work to 
do and it had no time to go out of its way to discuss a question 
of detail in the scientific work for the eradication of disease. So 
much by way of introduction. 
I desire to show now that I am not afraid to meet the doctor’s 
facts in a fair discussion before a professional audience. 
He begins as follows: “ It seems hardly necessary to say that 
pleuro-pneumonia or lung-plague in cattle is incurable and highly 
contagious; but the result of careful research and the experience 
of years shows that the contagion can only be communicated by 
contact with the living diseased animal. The disease is so insid¬ 
ious that it has only been after the most careful and thorough 
tests that this decision could be arrived at.” 
Is this one of the facts which the doctor referred to in his 
letter ? If so, I must respectfully but firmly object to it. The 
experience of years has shown nothing of the kind but, on the 
contrary, cases are recorded from the beginning of intelligent 
observation of lung-plague to the present time, which show con¬ 
clusively that contact with the living diseased animal is not neces¬ 
sary for the contraction of the disease. So with experiments— 
some have given negative results and some positive results, the 
same as do all experiments in every department of science. In 
chemistry every experiment does not succeed even when we think 
it ought. But you cannot build up a science upon the negative 
results of experiments; it is the positive results which are 
