88 
Utilisation of Town Setoage. 
the basis of any contract between town and country in the matter. 
The amount of nitrogen in sewage, in the forms of ammonia and 
nitric acid, affords the best indication of the amount of human 
excrements it represents, and hence it is the best guide as to the 
probable amount of the other valuable constituents. The relative 
value of the sewage might, therefore, be estimated according to 
the average number of grains of ammonia per gallon. 
The question now at issue, it must be remembered, is not 
whether the constituents of human excrements, if presented to us 
in a concentrated, dry, and portable form, might not then be 
applicable to all crops, to those under tillage designed to ripen 
^ their seeds, as well as others, but whether those same constituents 
distributed through enormous bulks of watei-, as under the pre- 
sent, and rapidly extending system, can be so applied ? 
, No one will doubt that if the sanitary requirements of the nation 
could be attained by any system which would preserve the excre- 
ments of the population free from admixtuie with water, and pre- 
sent them for use, at once undiminished in value by decomposi- 
tion, and in a portable and innoxious condition, the land of the 
country devoted to the growth of human food might, by their 
application to it, be greatly increased in its productiveness. 
• The question of the sanitary arrangements of our towns was 
taken up by engineers" before agricultural chemistry was much 
studied, and they have committed us to plans which, though 
they effectually remove the noxious matters from our dwellings, 
must greatly limit the area, and mode of their agricultural 
utilisation ; and which, at the same time, have tended greatly 
to the pollution of our streams. To say nothing of the enormous 
cost that would bo involved in entirely subverting the present 
methods of removing the excrements of the inhabitants of our 
large cities from their dwellings, it must be admitted, that no 
feasible scheme has yet'^been proposed by which this could be 
accomplished without the use of water. Such is certainly a great 
desideratum ; but perhaps a consummation more to be w'ished 
than expected. 
It is, perhaps, more probable, that by a reduction in the water 
supply, or by a more effectual separation of the sewage from the » 
rain-fall, town populations may succeed in producing for the use 
of the farmer a less diluted sewage. But, in the mean time, we 
must deal with the sewage as we find it ; and the price which the 
farmer could afford to pay for it would certainly offer no induce- 
ment to capitalists to invest their money in distributing it in 
small quantities over extensive areas. The only persons bene- 
fited b> such a scheme, would be the contractors, and others, 
engaged in carrying out the undertaking. 
