450 TJie Country Gentlemaiis Magazine 



Then, adds the report, " as the phosphate of less value. The proportion of ammonia is greater 



lime mixed with the sewage is derived from than I expected, and is probably due to a portion of 



,1 , 1 1 1 J the urine compounds being precipitated by the lime." 



the parent source — namely, bone-ash — and ^ & t- r j 



as the material in the recently precipitated It will be observed that, from the imper- 

 state is at least as effective a purifier of ^ect drying, the mass contained about one- 

 sewage as any of the precipitants which have fifth of its weight of water ; so that, with more 

 been tried — the whole of the manurial con- efficient drying, the manure would contain a 

 stituents of sewage capable of precipitation larger proportion of valuable ingredients than 

 are coagulated and carried down by it in the appears in this analysis ; while, with more 

 manure ; while, at the same time, the phos- perfect settling in the tank, the quantity col- 

 phate of lime is itself a valuable fertilizing lected from a given volume of sewage would 

 agent." Hence, the resulting manure is in be greater. According to Mr Sibson's scale 

 a much more concentrated form than when for the valuation of manures, precipitated 

 bulky materials of little value are mixed with phosphates should be reckoned at 3s. per 

 sewage for the purpose of precipitation. A unit, and ammonia at 20s. per unit, making 

 sample gave the following analysis : — the manure of the above sample worth jQ^ 



Moisture 19.04 per ton. Drier, of course it should be worth 



Organic matter- 15.26 more. In the experiment made upon more 



Precipitated Phosphate of Lime 23.14 than 3,000,000 gallons of sewage, the total 



Insoluble Phosphates 3.80 ^^eight of solid manure obtained was 50 per 



Sulphate and Carbonate of Lime and Lirne , ,, , ^ . , . , 



^ , . , ,^ ^^ cent, greater than that of the materials em- 



uncombmed I9'25 ° 



Alkaline Salts and Magnesia 3.14 ployed for precipitation. In concludmg his 



Insoluble matter 16.37 repoit, Mr Sibson says : — 



" The manure will be worth a fair market value, 



sufficient, I should imagine, to allow of the process 



• Contamuig nitrogen 1.20; equal to ammonia 1.45. ■. • .- 1 ■ j c u ™ „ v; 



'^ ^ ' ^ ^-^ being remuneratively earned on. Such a composition 



Mr. Sibson remarks : — will allow of a bona fide competition with other 



" It will be seen to contain about 22 per cent, of manures in the market ; and this I consider the chief 



phosphate of lime in the precipitated state, and about point of superiority of the process as compared with 



xYz per cent, of ammonia, with other constituents of some others in use for dealing with sewage." 



SE WA GE—FIL TRA TION AND IRRIGA TIOK* 



BY MR J. WIGGIX. 



THE subject of town sewage in its 

 economic application to agriculture, is 

 of national importance, and is beginning so 

 to be recognized. It is necessary to enter 

 briefly into the subject of the relation of 

 sewage to the health of town populations, 

 and of the urgent necessity to do something 

 in settlement of the question which is now 

 forcing itself upon the attention of the autho- 

 rities of all our large towns. In its present 

 magnitude, it is of but recent rise. The 

 T-.,^ 1 i,„r^,„ .!,„ J j^^,p^|,^j^.^ Farmers' Club, 



difficulty has been chiefly caused by the 

 boasted civilization of modern times. For- 

 merly the drainage of our towns was a surface 

 one, the open gutters in our streets carrying 

 off the rain as it fell into the nearest river, the 

 small quantity of organic matter being oxidized 

 and rendered innocuous by the fullest ex- 

 posure to the atmosphere. The foecal matter 

 proper, together with the vegetable refuse and 

 ashes, were received into covered middens or 

 dust-bins, kept preserved from the rain, and 

 periodically carried away by farmers' waggons, 



