CHAPTER XXVIII 

 SOME PROBLEMS IN WATER BACTERIOLOGY 



JOHN F. NORTON 



University of Chicago 



The accumulation of epidemiological evidence relating drinking water to disease 

 began about the middle of the last century with the investigations of Snow, Budd, and 

 other English sanitarians. With the establishment of the germ theory of disease, it is 

 hardly surprising to find that some of the early bacteriologists were interested in the 

 micro-organic content of waters of all characters and to find them offering biological 

 methods to detect dangerous contamination of water supplies. Emmerich,' in 1878, 

 proposed the subcutaneous injection of water, or of extracts of residues left after evap- 

 oration, into rabbits. A water dangerous to health was supposed to produce a rise in 

 temperature in the animals and subsequent death. Koch suggested a gelatin-culture 

 method for determining bacteria in water as early as 1881, but it was many years be- 

 fore bacterial methods were sufficiently perfected to be of practical value. Mean- 

 while, the sanitary chemical examination was regarded as the best means for deter- 

 mining the potability of a water supply. Very early, however, sanitary chemists rec- 

 ognized that biological methods must eventually be of prime importance, although at 

 the present time certain types of information can still be obtained only through chem- 

 ical methods. William Ripley Nichols, in 1883, wrote, "There is reason to hope that 

 eventually the decision [i.e., selection or rejection of a drinking water] may be thrown 

 largely upon the biologist."^ 



Between 1892 and 1900 bacteriological technique was developed to an extent to 

 warrant some general agreement among bacteriologists in regard to methods for the 

 testing of water supplies and, perhaps to a less degree, the interpretation of the results 

 obtained. The laboratory procedures were brought together in the first edition of 

 Standard Methods of Water Analysis? The fifth edition was published in 1925.'' While 

 the periodic publication of these standard procedures establishes reasonably satisfac- 

 tory routine methods for water examination, these methods cannot and should not be 

 regarded as terminating all problems of sanitary bacterial water analysis. A similar 

 statement might be made concerning the establishment of standards for the purity of 

 water supplies^ — a necessary and useful procedure but one which must be constantly 

 subject to revision. The development of more satisfactory methods, from the stand- 

 point of both accuracy and speed, represents, however, only one of the present prob- 

 lems confronting the water bacteriologist, although it must be admitted that the 



' Emmerich, R.: Ztschr.f. Biol., 14, 563. 1878. 

 ^ Nichols, W. R.: Water Supply, p. 89. 1883. 

 3 /. Infect. Dis., Supp. i. 1904. 



■t Standard Methods of Water Analysis. Am. Pub. Health Assoc: 1925. 

 s Advisory Committee on Official Water Standards: Pub. Health Rep., 40, 693. 1925. 



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