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L. MO LEAN. 
of disease, as I do; that is, that each specific disease has a specilic 
poison germ or seed which lives, grows, and has a being speci¬ 
fically distinct from each and all other germs. By specilic dis¬ 
ease I mean one which has its own peculiar characteristics, and 
which in its special appointing symptoms of reaction distinguishes 
it from all others; or v in other words, that all specific and con¬ 
tagious diseases are produced only by a minute living organism 
which cannot be spontaneously generated, but capable of an 
enormous reproduction when artificially cultivated for scientific 
purposes, or by the introduction of one single germ into the system 
of a fertile subject, affording more than sufficient to contaminate 
a whole continent. They are so exceedingly small that they can 
be readily carried in the atmosphere and so deposited in wounds, 
and it is by giving credit to this fact that we who have in our 
practice adopted the principal of antiseptic surgery can account 
for its beneficial results. They may be inhaled or swallowed in 
the food or drink; that many of them are propagated in the soil 
or water, such as those of anthrax, is an admitted fact, and al¬ 
though we have no proof of the germs of contagious pleuro-pneu- 
monia propagating themselves outside of the animal system, still 
there is ample authority that they do for a long time, in a suitable 
medium, resist destruction, while the life history of the germs of 
epizootic aptha, in or outside of the animal system, is one of 
very short duration. 
Now it is admitted that the exhalations of an animal affected 
with pulmonary tuberculosis, contagious pleuro-pneumonia, etc., are 
largely charged with the germs of such diseases, and taking into 
account the exceptional affinity milk exhibits for the absorption 
of volatile matter, and how readily it becomes contaminated with 
diseased germs outside of the animal system, thereby becoming 
one of the most effective carriers of contagion—it absorbs them 
readily, is very retentive and is a wonderfully fertile soil for their 
development—you will at once see the imperative necessity of 
guarding against its contamination. This supervision should 
begin in the stable where the cows are milked, which should 
be clean, well lighted and ventilated, emanations from putrifac- 
tive or decomposing agents being strictly guarded against. 
