130 
HAROLD C. ERNST. 
vice of the veterinarian to “ kill the cow and stop using- the 
milk” much more sound than it appeared to the minds of the 
medical gentlemen who “laughed ” at him at the time it was 
given. 
It is my hope within the coming year to collect a series of 
clinical observations which will be of interest and some ser¬ 
vice in elucidating the question of how many cases of tuber¬ 
culosis occur which produce suspicion in the minds of medical 
or veterinary attendants of having an origin in the milk from 
infectious cows. 
It is upon this question of possible danger from the domes¬ 
tic animals—especially cattle—that much recent work has 
been done, but the subject has been by no means exhausted. 
If there is danger to human beings from the widespread 
existence of tuberculosis among cattle, some sort of restrictive 
measures must be taken, by means of which this danger can 
be lessened. At the same time legislation calling for so much 
pecuniary loss as would be the case if the present supply of 
tuberculous cattle were to be destroyed, can only be asked for 
with a backing of as much carefully gathered scientific evi¬ 
dence as can be obtained, and it is the part of preventive 
medicine and the experimental method to furnish some of this 
evidence. 
Through the liberality and broad-mindedness of an asso¬ 
ciation of gentlemen in Boston, it is possible to present the 
results of certain experiments undertaken to determine the 
question which is expressed in the title of this paper. “ How 
far may a cow be tuberculous before her milk becomes dan¬ 
gerous as an article of food ?” is an extremely important point 
to decide. If it be considered already settled and Koch’s dic¬ 
tum be accepted, that there is no danger in the milk, if the 
mammary glands be not affected, then there remains only for 
the veterinary surgeon to determine the existence of such 
lesions, and restrictive measures can go no further. If, how¬ 
ever, the milk from cows with no visible lesion of the lacteal 
tract be shown to contain the specific virus of the disease in a 
not inconsiderable number of cases, and if this milk be shown 
to possess the power of producing the tuberculous process 
