134 J. ASHBURTON THOMPSON. 
say for the present purpose—is that the people of the town I have 
named, which is supplied with water, which has an area of about 
six square miles of alluvial soil, and a length of roads of about 
forty miles, are prepared to pay as follows for their new pail- 
system :—There are 1,600 houses; an annual charge of £1 7s, 
will be made for each pail, and therefore the total sum they will 
annually pay will be more than £2,160 (for a good many houses 
will require more than one pail). Now I have calculated that 
£2,160 a year is the sum necessary to pay four per cent. upon, 
and to extinguish in the course of sixty years, a loan of about 
£48,000. The question I propound is, therefore, this: Could not 
a system of sewerage be furnished to such a town for so much less 
than £48,000 that the annual payment of £2,160 would provide 
for working expenses and maintenance as well as for construction? 
I believe that there is no doubt at all about this—that the 
scheme would fall through at once if a condition were that the 
combined or the partially-combined system should be adopted. 
The large size of the conduits necessary under either of these plans 
would be an insuperable obstacle on the score of cost in relation 
to the money conditions by which I propose the discussion should 
be limited. The separate system alone seems to come within that 
limit, and to that I wish to direct your attention. That system, 
as you know, is designed to carry off sewage alone. It is designed 
to exclude every drop of rain-water and every drop of subsoil 
water ; and practically, in the many places where it has been 
successfully carried out, it does convey besides sewage only the 
quantity of water necessary for flushing purposes, which is sup- 
plied to the sewers from the water-mains at suitable points, in 
definite quantity, and at known intervals of time. The quantity 
of liquid that has to be carried on this system is, therefore, prac- 
tically equal to the quantity of water supplied to the town. That 
clean water is brought in by small pipes ; after it has been fouled, 
why should it not be carried out again by comparatively small 
pipes? That question indicates the view that was taken by those 
who designed the separate system, and who have of late years. 
