326 REPORT— 1869. 



Sewage dis- Sewage Contents of 



charged into used tor pits carted 



rivers &c. irrigation. away. 



Towns com- ] f Water-closets general 29 26 ^1 



pletely sew- >■ 48 -^ Privies 12 I 15 



ered J [ Both used 7 2 5 J 



Towns parti- 1 f Water-closets general 12 9 ^ ] 



ally sewer- 1 48 1 Privies 22 17 2 I 18 



ed J [ Both used 14 12 J 



rr, .If Water-closets used . . 1 ] 



Towns not [. ^ J Privies 6 4 I 5 



sewered.. J ^^^^^ 4 1 



Total number 107 



It will be evident that, according to local conditions, there will be great dif- 

 ferences in the nature of the liquid sewage of different places, and that even the 

 contents of pits, cesspools, &c. will vary, according as the soil is readily or 

 slightly permeable. The amount of the water-supply and the admission or ex- 

 clusion of surface-water from the sewers will also be of influence in this way. 



Total Quantity and Amount of Liquid Sewage. — Among the 96 places 

 where there is a system of sewerage, either general or partial, combined 

 with water-closets and a copious supply of water, the minimum daily quan- 

 tity of liquid sewage discharged varies from 20,000 gallons as at Alton, to 

 17 million gallons as at Birmingham, and 130 million gallons as at Liverpool. 



The storm-discharge at places where the surface-water is admitted to the 

 sewers varies from one and a half to twenty times as much as the discharge 

 during dry weather, and at places where the surface-water is wholly or par- 

 tially excluded it varies from one and one-tenth to seven times as much as 

 the dry-weather discharge. 



The average amount of liquid sewage per head of the population in places 

 where the surface-water is admitted to the sewers varies from 10 to upwards 

 of 100 gallons, and at places where the surface-water is excluded it varies 

 from 6 to 100. 



Treatment of Liquid Sewage. — At 15 of the places which are sewered 

 wholly or partially, the liquid sewage is subjected to treatment either by 

 allowing it to remain for a time in settling-tanks, from which the deposit is 

 occasionally removed, as at Burton-on-Treut, Birmingham, Epsom, Fareham, 

 and Audover, or by filtering, as at Uxbridge and Eahng. 



In eight instances deodorizing materials are added to the sewage. Lime and 

 carbolic acid are used at Carlisle and Harrow, lime alone is used at Leicester, 

 lime and chloride of lime at Luton, perchloride of iron at Cheltenham, perchlo- 

 ride of iron and Hme at Northampton, ferruginous clay treated with sulphuric 

 acid at Stroud, and at Leamington the lime treatment has lately been super- 

 seded by the method proposed by Messrs. Sillar and Wigner. By this treatment 

 the sewage is clarified, and a deposit is separated which is sold as manure. 



In regard to the effects thus produced, it is stated that at Leicester the 

 sewage runs off as pure as ordinary rain-water ; at Ealing it is said to be free 

 from smell, colourless, and harmless to vegetable or animal life ; at Stroud 

 and Luton the effect is stated to be satisfactory. At Harrow the nuisance is 

 said to be somewhat mitigated, and at Abergavenny the stench is said to 

 be abated by the treatment of the sewage. At Bury St. Edmunds upward 

 filtration through charcoal and gypsum has been abandoned as too costly and 

 in favour of irrigation. At Banbuiy treatment of the sewage has failed, and 

 irrigation is now resorted to. At Hereford, where it was proposed to be 

 adopted in the Parliamentary plans, it has not been tried, on the score of ex- 

 pense. At Tonbridge it is about to be tried ; and at Hastings and Cambridge 

 experiments are being made. 



I 



