Public health laboratory work, including methods employed in bacteriological research, with special reference to the examination of air, water and food contributed / by Rubert Boyce.

  • Kenwood, Henry R. (Henry Richard), 1862-1945.
Date:
1893
Catalogue details

Licence: Public Domain Mark

Credit: Public health laboratory work, including methods employed in bacteriological research, with special reference to the examination of air, water and food contributed / by Rubert Boyce. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    CHAPTER IV. The Analysis. It has been said, and truly so, that so small an amount of organic matter as would not call for con- demnation in the water, may yet contain the specific germs of disease, and that therefore it is only from the results of a bacteriological combined with a chemical examination, that a water may ever be classi- fied as safe. At present, however, there are many difiiculties to surmount before most of the specific germs can be identified as such in a water, and in the main a chemical analysis may be held to be very reliable ; for it is logical to contend—and experience supports the contention—that organic matter being the food pabulum for specific micro-organisms in water, the probability of their presence should bear a direct ratio to the amount of such organic matter present. At the very outset it must be realised that in drawing a conclusion as to whether a water is fit for human drink, organic matter (since an analysis mainly aims at detecting this) will give evidence of its presence in most of the steps which form a complete analysis, and that it is this collective evidence which mainly deter- mines a conclusion, rather than the evidence which any one special test may ofifer. This point is well illustrated in the physical characters of water, for whereas polluted shallow well waters are notoriously often clear, spark- ling, and pleasant to the palate (though affording direct