MTLK FROM TUBERCULOUS COWS. 
133 
of the infected milk by injection into the abdominal cavity of 
guinea-pigs with the usual precautions. His results were as 
follows: 
1. Milk was used five times from cows affected with a high 
degree of general tuberculosis in all the organs. 
2. Milk was used six times from cows with only a moder¬ 
ate degree of disease. 
3. Milk was used nine times from cows in which the dis¬ 
ease was localized in the lung. 
From these twenty cases the milk was proven to be infec¬ 
tious in eleven. The percentage of positive results in the ani¬ 
mals when arranged in accordance with the three groups 
above given was 80 per cent, in the first group (milk from 
cows in a very advanced stage of the disease), 66 per cent, in 
the second group, and 33 per cent, in the third. He found 
the bacilli in only one of the specimens of the milk, and con¬ 
siders that this, therefore, shows that the inoculation experi¬ 
ments are the more certain guide as to whether the milk is 
infectious or not. 
These results are extreme^ interesting, although they do 
not lay as much stress as do mine upon the presence or ab¬ 
sence of lesions of the lacteal tract. 
The experiments which I am able to report* have been 
made possible by the liberality of the Massachusetts Society 
for Promoting Agriculture, which became interested in the 
question some time ago, and has put it in my power to carry 
them on. They have given everything in the way of pecu¬ 
niary and moral support that the work has required ; my own 
part has been that of general director, and I have had asso¬ 
ciated with me during the whole time the Society’s veterinar¬ 
ian, Austin Peters, D.V.S. For the last year I have also had 
the very valuable aid of Dr. Henry Jackson and Langdon 
Frothingham, M.D.V. 
All of the inoculation experiments and most of the micro¬ 
scopic work have been done in the bacteriological laboratory 
*The full notes of these experiments will be found in the Transactions of the 
Association of American Physicians, vol. iv., 1889. 
