142 J. ASHBURTON THOMPSON. 
experiment which will serve to illustrate the small size of outfall 
sewer usually necessary under this system. It was in England 
that the use of pipe sewers, and their superiority, was first the 
subject of scientific enquiry and was first demonstrated and advo- 
cated in consequence; anda report by the General Board of 
Health dated London, 1842, has the following example among 
many others: The sewage from 1,200 houses was actually carried 
in a combined sewer which had a sectional area of fifteen square 
feet. For the sake of experiment a fifteen inch glazed e. w. p. 
was laid on the invert at a fall of one in one hundred and fifty-— 
three, and the sewage was conducted through it. It was then 
found that the average flow per house was fifty-one gallons per 
day, and therefore that the whole flow would have passed through 
a five inch pipe with the fall mentioned running full bore. So 
that it is clear, both from this and from the presently existing 
results of actual practice, that an outfall of more than fifteen 
inches diameter could seldom be required ; and back of it there 
would be only some comparatively short lengths of eight inch 
sub-main. The greater part of the system would consist of six 
inch laterals and four inch house connections. Now I will just 
repeat the question which I asked at first: ‘Is it not possible 
to furnish a country town of 1,600 houses which is already 
copiously supplied with water with a complete system of sewerage 
—to provide for construction, maintenance, and working-expenses 
—out of an annual payment of £2,160, which represents the 
annual sum required for interest and repayment within sixty 
years of a loan of about £48,000?” 
* * * * * * * 
Addendum.—It will be noticed that the above arguments are 
nearly those adduced in favour of what is now sometimes called 
the “Shone system.” I believe its evolution was as follows: Mr. 
Shone invented that very useful and successful apparatus, the 
ejector. It can be used and will succeed, however, only where 
the amount of work to be done is, within narrow limits, constant 
—as applied to sewerage, therefore, only when the pumping area 
ss a 
