2 BULLETIN 369, U. S. DEPARTMENT OF AGRICULTURE. 
cent) desired no rigid standard; only one desired a standard of no 
B. coli in 10 cc quantities: thirty-five (85.4 per cent) desired to apply 
the Hygienic Laboratory standard or one more rigid; eight (19.8 per 
cent) would tolerate no B. coli in bottled waters; one of the five bac- 
teriologists desiring no rigid standard considered water to be suspi- 
cious if three 10 cc portions show B. coli. 
We have a right to demand that bottled water shall first of all be 
clean. Whatever other qualities it may claim or offer are secondary 
to cleanliness. In a study, therefore, of the bacteria found, we have 
a right to consider them not only as possible evidences of danger to 
health but as indices of conditions in the bottling room for which 
the operator is clearly responsible. 
SIGNIFICANCE OF BACTERIA IN POTABLE WATERS. 
It is understood that natural waters may contain bacteria winch 
multiply in the presence of very small amounts of organic matter. 
Bacteriologists who have worked with distilled water are familiar 
with the micrococci which multiply rapidly therein when the per- 
centage of organic material is extremely low. The presence, there- 
fore, of a large number of organisms in waters which have been 
bottled for several days or weeks has little significance unless the 
characters of these organisms are more or less definitely known. 
The presence of B. coli in large numbers in waters is universally 
considered as an indication of the possible presence of its dangerous 
associates. The conditions under which waters are bottled and 
held and the mineral substances present may, in some cases, exert 
influences upon the multiplication of B. coli differing slightly from 
the effect of surface or well waters in nature. Preliminary studies 
in this laboratory indicate an immediate decrease instead of any 
possible increase of B. coli in freshly inoculated bottles of certain 
spring waters. 1 Houston 2 found that B. coli disappeared in stored 
water from the River Lea. Dunham 3 observed that distilled water 
enriched with either hay infusion or nutrient broth (1 cc in 1 liter) 
and inoculated with over 20,000 B. coli showed a marked reduction 
of the total number of B. coli at the end of 24 hours. He also reported 
that sterile water inoculated with pollution from ordinary soil does 
not show an appreciable number of B. coli. 
It may, therefore, be assumed that bottled waters in which B. coli 
are found hi appreciable numbers contained approximately all of 
those B. coli (if not more) when they left the springs or bottling 
1 Browne, W. W. (Jour. Infect. Dis., v. 17, No. 1, 1915, pp. 72-78) finds multiplication of B. coli in stored 
water, but an analysis of his experiments shows that the water used was so enriched as to be no longer 
comparable to stored spring waters. 
- Houston, Reports on Research Work, Metropolitan Water Board, London, 1907. 
3 Dunham, E. K., Value of bacteriological examination of water from a sanitary point of view, Jour. 
Amer. Chem. Soc, v. 19, No. 8, 1897, p. 591. 
