392 
Seioage- Farming. 
during the last few years towards tlie solution of tliis problem 
than had been before attempted. Sewage-farming has become 
an established fact in every quarter of the kingdom, and, thanks 
to the intelligence and zeal of some of its promoters, every day 
is adding to our knowledge of the principles on which it should 
be conducted. 
Modes of Utilizing Sewage. 
I shall briefly refer to some of the various modes which have 
hitherto been adopted on a large scale for the utilization of 
those substances which are included in the definition of sewage 
which I have adopted. The more important of these may be 
classified as : — 1, the Earth System ; 2, the Precipitation 
System ; and 3, the Water System. 
The first of these has received considerable attention of late 
years. It is probable that no other mode approaches it in its 
power of retaining the value of the solid parts of the excreta of a 
population. Why then has it met with so little favour ? Because 
it is impracticable in any but small villages or isolated dwellings, 
and because the application of it in towns (if practicable) would 
still leave undisposed of a vast quantity of offensive matter which 
must be got rid of by means of water. It is not only the excreta 
of the population which find their way into town sewers, but a 
thousand sources of pollution, many of them at least as offen- 
sive as those with which the earth-closet would alone deal. It 
is a fact that the sewage of towns where the " midden system " 
is adopted is nearly equal in value to those where the water-closet 
system is in use. The middens are cleaned out periodically by 
scavengers appointed for the purpose, and on notice being given 
to the proper authority, the contents being carted away and sold 
for manure. This course would seem to prevent the possibility of 
the contamination of the sewage Avith any large proportion 
of foecal matter ; yet the experiments instituted by the Rivers 
Pollution Commissioners have placed it beyond a doubt that 
the sewage from these towns is to the full as offensive as, 
and nearly equal as a manure to, that of the others. The 
reason seems to be that much of the soakage from the middens 
finds its way into the sewers, and that more people generally 
contribute to the sewage in midden than in water-closet towns. 
It is evident that the earth-closet system can no more deal with, 
what I may call, the waif-and-stray elements of sewage than the 
midden, and for this reason it is found impracticable in towns. 
I have stated thus much of the dry-earth system, because 
its value in an agricultural point of view is considerable 
under some circumstances, and not because it is applicable 
