1890. | RAFTER AND MALLORY-—ENDEMIC OF TYPHOID FEVER. 81 
of the Lime-Kiln Gull creek at Mill street is above the ground water, 
and the well known fact, that while this stream is always flowing further 
to the south, the section through the village from Mill street to Main 
street is frequently dry, serves to indicate forcibly that considerable 
quantities of water flow from the village toward the main creek. 
Below Mill street, to the north, it appears probable that the eleva- 
tion of the ground water is about the same as the bottom of the Lime- 
Kiln Gull creek, and this further agreement of physical fact with the 
results of chemical and bacteriological analysis is an additional argu- 
ment in favor of the truth of the evidence of increased contamination 
of the water of this part of the Lime-Kiln Gull creek, as presented in 
the preceding. 
Plate g is to scale, and illustrates the actual relation between a 
privy, the ground water, and one of the village wells. This plate illus- 
trates a typical case, and is the prototype of a number of others in the 
village. 
The germ theory of typhoid is so firmly established by actual 
experimental evidence that all who are fully conversant with the 
evidence now admit its validity, and we are therefore at once confronted 
in such a study with a very pertinent question ; namely, assuming it to 
be true that a portion of the ground water of the village of Springwater 
was in October and November last permeated with typhoid bacilli, and 
further assuming that the ground water carrying such bacilli flows 
directly into the Springwater creek, what is the probability of these 
bacilli ever arriving in a living staté at Rochester ? 
Stating the case in this way at once brings us to consideration of 
the length of time that pathogenic germs will survive when placed in 
potable.water, in which presumably the ordinary bacteria of putrefac- 
tion are present. Professor S. G. Dixon, of the University of Pennsyl- 
vania, has recently experimented on this point and found that the 
bacilli of typhoid, placed in Schuylkill water, lived not longer than five 
days. This result, it is concluded, was produced by the antagonism of 
the bacteria of putrefaction which the water contained, they having, by 
virtue of superior numbers, either crowded out or actually consumed 
the bacilli of typhoid. 
We note, however, that Professor Dixon experimented with pure 
cultures of the typhoid bacillus. It is not unlikely that typhoid bacilli 
finding their way into potable waters enveloped in masses of fecal 
matter might live a much longer time than five days, by reason of this 
environment. 
6. Proc, Rocu. Acap. OF Sc., Vol. 1, Sept. 1890. 
