IOWA ACADEMY OF SCIENCES. 
‘93 
In comparing the results of the second analysis with the 
first analysis, it will be noticed that the amount of nitro- 
gen as nitrates, has increased from 24 parts to 40 parts per 
million, while the albuminoid ammonia has decreased. 
These results indicate that the nitrogen in the organic 
matter which was present in the water has been changed 
during the process of nitrification into nitric acid. This 
change has probably taken place during the passage of the 
water through soil in which the conditions were favorable 
for the nitrifying process. 
When inquiries were made regarding the use of this 
well, the claim was made by the owner that it was not 
used, but that a deeper well, which was near the shallow 
well, furnished the water. It was discovered, however, on 
visiting the place one morning, that a bucket of water was 
being pumped from this well for drinking purposes, and 
was supplied to a number of men working on the railroad 
near the place. The deep well proved to have a very lim- 
ited supply of water when tested; and it was then claimed 
that the shallow well water was used only for washing out 
the milk cans, etc. A case of typhoid fever had occurred 
in the family of the farmer during the summer, and on 
tracing the case it was found, that this case and the epi- 
demic were closely related when consideration was given 
to the time necessary for the development of the disease 
The number of cases were from forty-five to fifty, and almost 
the entire number of patients came from those who used 
the milk furnished by the farm with the contaminated 
well. It was also found on investigation by the physician 
that a number of the laborers on the railroad had devel- 
oped cases of typhoid fever. The conclusion naturally 
reached is, that the well was contaminated from 
some source, and at the time at which the case of typhoid 
fever was in progress in the family of the farmer, contained 
the typhoid germ. The use of this water for washing milk 
cans without boiling, transmitted the germ to the milk, 
and by the milk to the digestive system of the persons 
using the milk. 
