Outlines of bacteriology (technical and agricultural) / by David Ellis.

  • Ellis, David, 1874-1937.
Date:
1909
Catalogue details

Licence: In copyright

Credit: Outlines of bacteriology (technical and agricultural) / by David Ellis. Source: Wellcome Collection.

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    lias been shown that some of the bacteria that are present in the eflluent are capable under certain conditions of engendering diseases of various kinds, so that it is considered dangerous to allow effluents to enter streams, the waters of which in the immediate neighliourhood are used for drinking purposes. There is at present no known method which can bo absolutely relied upon to free sewage altogether from the germs of diseiise, and we are not yet in possession of much definite information as to the e.xact extent of the danger arising from the effluents of the existing methods. Houston’s work indicates the “inadvisability of relying on septic tanks, contact beds or continuous filters to remove altogether the element of potential danger to health associated with the discharge of effluents from these proce.sses of seivage treatment, into (Irinking-water streams.” There can, however, be no doubt that the treatment of sewage is highly beneficial to the community, and we may conclude with Dr. Reid’s declaration that if he had to choose between “ the di.scharge into a stream of the crude sewage of 29,000 people ” and that “of the treated, therefore non-putrefactive, sewage of a popu- lation of 420,000 odd,” all he could sa\' would be “it would not be the crude sewage of 29,000 people which he should select in the case of a stream over which he had control, as an alternative to the treated sew’age of a population, no matter how large.”