556 
SANITARY NOTES ON POTABLE WATER. 
perhaps even of an organised nature, there cannot be the 
least doubt that it will also be subject to that general rule. 
But this does not in the least exclude the possibility that in 
the course of intermediate putrefactive stages, fermentation 
may not be even favourable to the development or multipli¬ 
cation of the contagion. Do we not see every day that 
plants feed and thrive on fermenting matter, and yet that the 
same plants ultimately become its prey ? These considera¬ 
tions may explain apparently contradictory statements. 
The probable absence of any connection between fermen¬ 
tation and contagia is suggested in my notes by only one 
single statement, which is the result of an experiment by 
Birch-Hirschfeld.* On injecting into the alimentary canal of 
rabbits fcecal matter infected with the virus of typhoid, both 
in the fresh state and after keeping it for several days, he 
v/as not able to discover any difference in the virulence 
of the symptoms. Considering the comparative immunity 
which rabbits enjoy from the effects of typhoidal discharges, 
th is experiment would seem to require further confirmation 
before being accepted as a final proof that putrid matter has 
no influence on the contagion of typhoid. 
By far the largest number of statements is opposed to 
the views to which I have hitherto referred, being more or 
less favourable to the supposition that the virulence of con¬ 
tagia, generally speaking, is increased under the influence of 
fermenting matter. 
The views held by Professor Tyndall are well character¬ 
ised by the manner in which he endorses in his treatise 
‘ Fermentation and its Bearings on the Phenomena of 
Disease 9 certain experiments made by Dr. Sanderson.-f The 
latter inoculated mice subcutaneously with the blood of an 
animal suffering from splenic fever. The experiment was 
then varied, the blood being dried, permitted to assume the 
form of dust, the dust wetted, allowed to dry again, and left 
“ in the midst of putrefying matter.” After thus keeping 
the blood for four years, its action was as fatal as that of 
blood fresh from the veins of an animal suffering from 
splenic fever. These observations are of special interest in 
view of Davaine's experiment, to which we referred before. 
Dr. Bastian informs usj that epidemic diseases are fre¬ 
quently most fatal when they once break out amongst a 
people who are in the habit of feeding upon diet contain¬ 
ing much putrid matter, as for example the Kalmuck Tar- 
* Sander, ‘ Handbuch der Oeffeutlichen Gesuneheitspfiege, 5 p. 5G. 
t Fortnightly Review , November 1,1876, p. 568. 
J ‘ Beginnings of Life, 5 ii, p. cxxiv. 
