The Authors, some time ago, read before different Societies of
professional men, Papers[1] dealing with the Natural and Artificial
Purification of Sewage, and as these were favourably received, the
thought occurred to them that the time might be opportune for making
the information there given available for a wider public.
As, however, a mere republication of the Papers would have been
against the rules of the Societies concerned, the Authors decided to
re-write entirely the subject matter, and to bring it up to date, so
that the present publication is not a mere repetition of their old
Papers clothed in a new garb, but an entirely fresh publication, right
up to date.
The Authors hope that they have given the information in such a form
as to be readily available for District Councillors, Sanitarians, and
all interested in this complicated subject.
When considering natural and artificial sewage treatment, it ought to
be borne in mind that in the natural treatment we have to deal with
one treatment only, and that, in order to bring the results obtained
from artificial processes up to the same standard, the artificial
treatment ought to be supplemented by a treatment for the removal of
nitrates from the effluent, and another for the removal of pathogenic
micro-organisms, which means one treatment in natural, as against
three separate treatments in artificial purification.
In addition to this it must be understood that, owing to the great
losses by evaporation and by growing plants, which are continually at
work on sewage farms, especially during the summer months, when, as a
rule, the flow of water in the brook that takes the effluent is
smallest, the quantity of the effluent from the natural treatment is
probably only from one-half to one-third that resulting from the
artificial treatment, which is a point of very great importance.
If it can be proved to them that Nature is not sure and true enough in
its methods, the Authors are prepared to assist it with methods and
means produced by the inventive brain of man. But if such proof is not
forthcoming, they adhere—in preference to groping in the dark—to
Nature’s own methods, knowing from experience, that when allowed full
scope and fair treatment, it is most sure in all its ways. That will
not prevent them, however, from giving in the future, as they have
done in the past, the question of sewage treatment in all its aspects
their most careful consideration.
ALFRED S. JONES.
H. ALFRED ROECHLING.
LONDON: _September 15, 1902_.
[1] ‘Sewage Treatment: Science with Practice.’ By Colonel A.
S. Jones, V.C., C.E. Read at the International Engineering
Congress at Glasgow, 1901. And ‘The Sewage Question during
the Last Century.’ Read by H. Alfred Roechling, M. Inst.
C.E., F.G.S., F.S.I., etc., on December 2, 1901, before the
Society of Engineers, and awarded the Gold Medal of the
Society.