SEWERAGE OF COUNTRY TOWNS. 137 
the construction of a few surface channels will not do the smallest 
appreciable extra harm to the public health, even if they should 
themselves be always foul—which, however, they need not be, 
But it is almost childish to discuss the matter in that way. 
Regular and effectual scavenage is as necessary to preserve the 
public health as any sewerage ; and it should be borne in mind 
that scavenage and sewerage are complementary to each other— 
are, in fact, but diferent branches of the same business. I have 
long had in mind the arguments for admitting surface waters to 
sewers which are based upon their foulness, and at last I have 
come to the conclusion that it is monstrous that questions of 
sewerage should have remained so long complicated in that way— 
that such a consideration should for so long have been allowed to 
prevent poor towns from having any sewerage at all, and should 
for so long have prevented richer towns from having systems of 
sewerage constructed upon those principles on which alone sewage 
can be safely carried and profitably utilized. 
But a further difficulty attaches to this matter, to which more 
weight must be allowed when the sewerage of established cities is 
under consideration. It is the difficulty of “‘back-yards and back- 
roofs.” When the Western Suburbs sewerage scheme was on the 
point of authorization a discussion was raised—then, at the last 
moment, and when nothing but confusion and delay could come 
of it—on this very question of separate sewerage. It may possibly 
be within the recollection of some here present that on that occa- 
sion I allowed the fullest weight to this difficulty of back-yards, 
and strenuously upheld the partially combined system for the 
parts of Sydney then to be sewered, at a meeting of the Engineer- 
ing Association of New South Wales. I did not choose then to 
consider what part of the Western Suburbs might fall under the 
conditions I am going to describe as free of all embarrassment 
from back yards, and to which the separate system wonld, in my 
Opinion, be applicable. A great part of them in all probability do; 
but still it was not worth while to raise the point at a time when 
large neighbourhoods, that had long languished through a period 
