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Scientific Memoirs by

of obtaining adequate supervision, absolutely essential for carrying out trenching,
is largely minimised, and with a proper integral system of removal is almost entire-
ly obviated, while the risks to health, to some extent incumbent on all methods,
are reduced to a minimum. In larger communities installations can be estab-
lished at suitable points, and so save the cost of large schemes for the devolution,
of all the sewage to a common outfall; smaller communities need not wait for the
large comprehensive schemes required by towns in or near which they are situated.
As regards the final disposal of the effluent, we have doubtless something yet
to learn, if it be desired to discharge it into a stream. Our own opinion has been.
stated, that no means of disposal can compare with land irrigation both for safety,
and for the return we desire in the shape of vegetables and other crops which,
will go far to recoup the expenses of the first cost of the necessary apparatus.
Still, where a foul nullah or water-course is the only resource, we may rest
assured that, so far as the chemical effect of the effluent is concerned, a great
purification of the stream is secured, from the biological and chemical forces,
which characterize the effluent (see Manchester experiments, independently
confirmed by those made by the writer at Simla, in 1899-1900).

III.

   We come now to a brief discussion of the practical application of the prin-
ciples which have been set forth in the preceding pages, and we must premise
that our object is "the perfect adaptation of drainage, water-supply and scavenage
to the purpose of carrying away, inoffensively, all refuse materials of life from the
person, the house and the environment, so soon as possible after their formation,
and with as near an approach as possible to one continuous current of removal,"*
and with this, their speedy, safe, complete and economical disposal.

   It is clearly impossible to indicate here in exact detail the precise measures ne-
cessary to achieve these objects, which must be grasped in their organic unity; the
special conditions of each community and locality must necessarily be studied and
the measures must be adapted thereto. What follows must therefore take the
form of general suggestion, which will not be found difficult of application, pro-
vided that the necessity for a radical reform of our present methods, and the prin-
ciples which should guide us to that end are accepted as an undeniable obligation
by those responsible for the lives and well-being of our troops.

   The subject on its practical side will be dealt with, briefly, under the follow-
ing heads: (I) removal of excreta and, polluted waste water; (2) disposal; (3)
water-supplies; (4) general remarks.

*Sir J. Simon (loc . cit .)