Sewage 



been screened in a heap, so that it has begun 

 to decompose, its value is considerably raised. It 

 must be cleansed of objects likely to hurt or hinder 

 the crops. That is why it is necessary to go over the 

 fields where town refuse is spread with a basket and 

 collect these foreign substances. As it very often 

 contains various seeds, it should only be applied to 

 cleaned crops ; also it could be used in market 

 gardens on the outskirts of towns where the cost of 

 transport is not high. On the spot where it is 

 bought on waggon or boat, the price should not be 

 more than one shilling per cubic ton. Very often 

 it wdll not be worth even as much as this if it has 

 to be carried any distance. 



Sewage. 



This is the matter passed off to the sewers of 

 to\vns, collected in reservoirs and treated in a manner 

 differing according to the system adopted. 



It includes human excrements, domestic sink 

 water containing animal and vegetable waste, slops, 

 blood from slaughter houses, stable urine, street 

 flushings which contain the droppings of animals, 

 the rubbish of markets and workshops, and the dust 

 formed by the wear of the materials of which the 

 roads are made. 



All this is turned into large cement tanks, and 

 allowed to subside, and the liquid on rising is drawn 

 off into another tank, and these decomtations are 

 continued until the residue deposited has become 

 quite insignificant. The deposits are treated in 

 turn. They contain a great deal of water, but they 

 are raised and allowed to dry and then converted 



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