191 
TABLE NO. 3. 
Hospital . 
Number 
of samples. 
j Number 
samples 
lost by 
acute 
1 death of 
guinea pig. 
1 
j Number 
samples 
remaining. 
Number 
samples 
positive 
for tuber- 
culosis. 
Providence 
2 
0 
2 
0 
Children’s 
1 
0 
1 
0 
Georgetown 
0 
1 
0 
Garfield 
2 
0 
2 
0 
Sibley 
....... 1 
0 
1 
0 
Orphan Asylum . . . 
1 
0 
1 
a 1 
Columbia 
2 
1 
1 
0 
Total 
10 
1 
9 
1 
Percent 
10 
90 
11.1 
a Both pigs from sample positive. 
RESUME. 
It will be seen from the above that of 272 samples of milk 19, or 18 
per cent of the samples, were lost by the animals dying in less than 
three weeks and before sufficient time had elapsed for them to develop 
tuberculosis. Attention is invited to the fact that the milk from some 
of the dairies killed acutely a high percentage of all of the animals to 
which it was given. 
Of the 272 samples 228, or 82 per cent, remained for study. 
Of the 223 that remained 15, or 6.72 per cent, contained sufficient 
tubercle bacilli to cause t} 7 pical tuberculosis in the inoculated animals. 
Of the samples of milk from 101 dairies, 2 were lost by acute death 
of the animals, leaving 102 ; the milk from 11 of these 102 dairies con- 
tained tubercle bacilli. This gives a percentage of 10.7 of the dairies 
examined showing tubercle bacilli in the milk supplied to their 
customers. 
Ten samples of milk were obtained from 7 charitable institutions 
of the District ; of these 10 samples, 1 was lost by the acute death of 
the animal, leaving 9 samples from 6 institutions for study. The 
sample from 1 institution caused tuberculosis in both guinea pigs in 
which it was inoculated. 
These results showing that approximately 11 per cent of the dairies 
whose milk was examined contained tubercle bacilli virulent for 
guinea pigs do not, however, give a fair idea of the frequency of the 
presence of tubercle bacilli in the market milk of the city of Wash- 
ington. Attention has already been called to the fact that w r hen two 
animals were inoculated with the same sample both did not always 
develop tuberculosis; this would indicate that the bacilli are so few 
in the amount inoculated that one of the animals by being a little 
