SEWERAGE OF COUNTRY TOWNS. 139 
But now opponents of the separate system will be ready to point 
out that surface waters must be drained off inhabited areas, and 
if the area be considerable the streams will soon accumulate; and 
if they are derived from a considerable paved area that they will 
not run very far before they become inconvenient or dangerous by 
mere bulk. Well, all that is true as far as it goes; but it hardly 
touches the point, even in large cities. The removal of sewage is 
one business, to be done in one way; the removal of surface waters 
is another business, to be done in another way. If this distinction 
be lost sight of, expense, inefficiency, and general confusion result; 
for the kind of provision necessary for sewerage is vastly more 
expensive than that necessary for drainage. It hardly touches the 
point, I said ; for Colonel Waring, although he does not press the 
adoption of the separate system in large cities—although he does 
not unconditionally urge it—has considered this point in detail, 
and the result of his calculations is that the length of underground 
drains to carry the surface waters in any place probably need 
never exceed one-fourth of the length of the sewers necessary in 
that place to carry the sewage. So, even under condition that 
storiawaters had to be carried underground as soon as they incon- 
veniently accumulated, it would be cheaper to construct separate 
channels for them than to enlarge the sewers to carry them. But 
this point has very little to do with such cases as T am now con- 
templating. There the inhabitants have already made such pro- 
vision as is actually necessary to carry off their surface waters ; 
and as to carrying them underground in any case, even in those 
Western Suburbs to which I alluded a moment ago, already a 
part of those accumulated streams is not so carried, but in two 
or three neighbourhoods open channels (such as I have had 
opportunity of recommending officially on several occasions) are 
coming into use. And so the matter might be cheaply managed, 
and quite efficiently, very generally. Surface waters are not 
sewage, and therefore—I say, therefore—should not be admitted 
to sewers. 
These surface waters become subsoil waters, except in case of 
storms. They should, we know, be drained off as quickly and as 
