112 
He gives the results of subsequent examination as follows : 
The Maugfall water arrives at Munich with five microbia 
per c.c. After twenty-four hours, being left under the 
conditions above described, the number of microbia is found 
to have risen to more than a hundred per c.c. In two days 
the figure reaches 10,500. In three days, 67,000. In four 
days, 315,000. And on the fifth day there were more than 
half a million of microbia per c.c.” 
It would appear from Dr. Leone’s further experiments, 
that the fact of the water being at rest merely has no in- 
fluence on the multiplication of the microbia. The water 
was agitated by means of a wheel arrangement, and the same 
results were obtained. It is further to be noted that, after 
attaining the maximum, the number of microbia gradually 
declined, so that a curve would be given by a graphic illus- 
tration. 
The results obtained by Dr. Smith from his hydrogen 
test, and by cultivation in gelatin, were approximately 
the same. Prima facie, however, it seems obvious that 
these results would be affected by the length of time which 
might have elapsed subsequent to the collection of the sam- 
ples. We must assume, of course, that multiplication would 
take place in the spring or stream as in the test vessels; but 
the water under natural conditions would be constantly 
diluted from the source, so that the proportion might never 
rise much above the minimum. In the test vessels all the 
succeeding generations would be retained in the confined 
space. It seems obvious, therefore, that the comparisons 
would be affected by the factor of time. Water tested imme- 
diately after collection at the spring would apparently give 
smaller indications of microbe activity than if retained for 
twenty-four hours or longer. Much, too, would depend on 
whether the testing took place after the maximum re- 
production had been attained, and the curve had taken a 
downward course. 
