594 
G. A. JOHNSON. 
Succinctly stated, the proposition's, that tubercular lesions, 
wherever found, are the direct results of the action of the tuber¬ 
cular bacillus ; and further, that the domestic cow is the natural 
harbinger of this bacillus ; or in other words, tuberculosis was 
primarily a disease of the bovine species, and is found in man 
and other animals as a result of transmission, brought about 
through the ability of the tubercular bacillus to adapt itself to 
the various conditions, as found in the various animals. 
I fully appreciate the fact that this position is not in accord 
with the prevailing thought of the medical profession ; but it 
would be a waste of time and energy, yours and mine, for me to 
present thoughts fully in accord with yours. 
Assuming that it is generally agreed that the disease is 
transmissible from one animal to another, and from various 
species to others-, man included, 1 shall confine my efforts to a 
brief resume of some of the facts that indicate that tuberculosis 
is naturally a bovine disease. 
Premises .—If we find that a certain disease is always preva¬ 
lent where certain conditions prevail, the world over, and that 
it is never prevalent where these conditions do not exist, we 
have at least very strong presumptive evidence that these par¬ 
ticular conditions must exercise a greater or less influence upon 
the distribution and spread of this disease. 
This fact having been established, it at once places the 
disease in a new light, and suggests very important factors in 
relation to the control or eradication of the disease. 
If this premise is tenable and susceptible of a logical deduc¬ 
tion, and I believe that it is, such factors should always be 
considered in dealing with any disease, but more especially a 
contagious one. 
In following out this thought, a brief examination of some 
of the various conditions in which we find tuberculosis most 
prevalent may present a new phase of the question. 
Climate .—While a dry, temperate climate may have more 
or less favorable influence upon the progress of the disease, we 
know that no set of climatic conditions, as to heat or cold, dry- 
