76 5Ik. Smith on Sewage Water of Toivns. 



trouble to make a survey of the surrounding country, and it will come 

 home to the experience of every farmer, that there is every where a great 

 want of manure to produce the fullest effect. If manure can be furnished 

 in this manner at half the cost of ordinary manure, and be laid on the 

 ground when the farmer wishes it, without carting over his land, with 

 very little trouble to himself, and with results beyond the average of ordi- 

 nary crops, there can be no doubt of finding customers every where. The 

 crops of the farmer who uses this manure will excite the jealousy of his 

 neighbours, which will lead them, I would almost say force them, fo follow 

 his example. 



The question of the disposal of the sewage water in the liquid form, 

 for agricultural purposes, being determined, the engineering of the system 

 of sewers will be greatly simplified and rendered independent of tidal 

 influence, as wells can be put down at points most convenient for the 

 drainage of specific areas, and for the transmission of the liquid by the 

 nearest route to the country. The sewerage should consist of a double 

 system of air-tight tubular sewers, the one to receive the sewage water, 

 the other to receive the rain water falling upon the streets and houses. 

 All the inlets being securely trapped, so as to prevent the escape of any 

 gas from the sewers, whatever gas may be generated must find its way to 

 the general outlet, when it can be passed through the furnace of the 

 pumping engine, and be thereby deprived of its noxious qualities, and be 

 thi'own into the air at a height above the streets and dwellings. 



In order to test the usefulness of the manure in the liquid form, Mr. 

 Smith said he had made extensive inquiries for several years. A number 

 of experiments had also been made with the view of testing the practica- 

 bility of dealing with it in the liquid form, and ascertaining the cost at 

 which it could be pumped into pipes, and thus conveyed into the country. 

 It was ascertained that sewage water can be conveyed, by pumping, ten 

 miles, and delivered on the ground for 3d. a ton, with a moderate profit ; 

 whereas, to cart a ton for ten miles costs 5s. The liquid is not only con- 

 veyed at this charge, but distributed. The expense of distributing liquid 

 manure by cart is considerable, and in the solid form it is more expensive 

 still. Mr. Smith next remarked that the sewage water of large towns 

 contains all the elements of the food used by the inhabitants and by 

 animals. These elements exist in the state of mechanical mixture, of 

 suspension, and of solution. A large dilution of these matters with water 

 not only deprives them of smell, but fits them better for being applied to 

 the land. The suspended matter moves easily in properly constructed 

 sewers, and can be conveyed with facility through pipes. The sewage 

 matter applied in the liquid form is much less liable to be washed away 

 by rain, than when applied in the solid state ; and besides, both chemical 

 investigation and the results of experience combine to show that solid 

 manure is less valuable than manure in a state of suspension or solution. 

 In the Meadows at Edinburgh, which are irrigated by sewage water, it is 

 found that the matter in suspension has a tendency to lodge at the roots 



