Sewage-Farming. 
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the beds abut, as far as possible, on the irregular boundaries of 
the farm, so that they may not interfere with the parallel lines 
of cultivation. I fixed the width of the beds at 30 feet, after a 
number of very careful experiments to ascertain what was, all 
things considered, the best and most convenient width of bed for 
the economical distribution of sewage ; and this bed combines 
other great advantages not connected with irrigation ; for the 
area of a bed is at once obtained in square yards with absolute 
precision by measuring the length and multiplying by 10. 
This, for selling market-garden crops, is a very great convenience. 
The half-bed of 15 feet from ridge to furrow is also a conve- 
nient width for harrowing, rolling, drilling, mowing, or raking 
'in twice,' as the farmers say. 
*' The sewage is delivered on to the farm by gravitation some 
20 feet below the higher portions of the farm. In order to reach 
these, I put up a sheet-iron trough on wooden legs, which reaches 
from the engine-house to various parts of the farm, where the 
level of the ground admits of the sewage being carried on in 
ditches, or carriers formed in low earth banks and lined with 
concrete. The concrete carrier is the best, but of course after a 
certain height it becomes too expensive and wastes much land by 
its spreading base ; hence the substitution of iron. Both are so 
constructed as to distribute the sewage to the minor gutters in the 
beds passed on the way, if desired, as well as to convey it to more 
distant parts. This the infinitely more expensive pipe used in 
some places would not do."* 
The map annexed, and Mr. Hope's description, will give a very 
clear idea of the mode which has commended itself most highly 
to modern authorities, but about the smaller details of which 
there is yet some dispute. The catchwater system, I have before 
said, yet finds its defenders, but it seems far better adapted for 
simple irrigation than for the utilization of sewage. This mode 
is so generally understood that it is unnecessary to explain its 
operation ; but it seems a self-evident proposition that sewage 
delivered over successive areas or beds cannot equally and satis- 
factorily irrigate them alike. This latter, however, should be the 
object, if any adequate money return is looked for. Every ton 
of sewage should be carefully husbanded, expended where it is 
required, and by no means allowed to run to waste, as some of it 
inevitably must, in the beds which it at first reaches, under the 
catchwater plan. 
The cost of the preparation of land will of course vary 
with circumstances and localities. At Aldershot, where much 
of it was levelled at great expense, it probably was not less 
* 'Sewage Irrigation.' A lecture by W. Hope, V.C., p. 11. Stanford, 1871. 
