ON THE TREATMENT AND UTILIZATION OF SEWAGE. 449 



Again, at Toubridge Wells " it was stated that a large field of turnips, 

 being infested with the fly, was flooded with sewage, which drowned the fly 

 and saved the crop, which is expected to turn out well but rather late." 



So far, then, as actual facts at present show, " there is no evidence that 

 entozoal forms of life are to be found on the farm at all in any stage of their 

 existence, or in the flesh of an animal fed exclusively for 22 months on sewaged 

 produce grown on the farm." (Eeport III. p. 189.) As far as the sani- 

 tary influence of sewage-farming is concerned, the Committee have retiu'ns 

 from eight places where it is at work. In no instance has any disease what- 

 ever been traced, either among the labourers on the farm or among the inha- 

 bitants in the vicinity, or among the cattle, to the sewage-farm. In two 

 instances it is reported that the health of the neighbourhood has improved, 

 and in several that the land has very much improved in value, and the pro- 

 duction of crops is much more certain. The note from Aldershot is, " Sani- 

 tary state of Camp and Barracks vastly improved. The land produces fair 

 crops under sewage, which before produced nothing whatever." 



Conclusions arrlvbd at by the Committee. 



I. All conservancy plans, including midden-heap and cesspool systems, 

 dry ash- and dry earth-closets, pail-closets, &c., are quite incompetent as so- 

 lutions of the general question of the removal of the refuse matters of a 

 population. 



Such plans deal with only a small part of the liquid manure ; towns which 

 resort to one of them require, therefore, to be sewered, and the sewage re- 

 quires to be piu'ified. 



The manure produced is in all cases (except in that of simple pails or tubs 

 where no extraneous materials are added) poor, and will only bear the cost 

 of carriage to a short distance, taking into consideration the cost of collection. 

 That produced by the dry earth system is, even after the earth has been used 

 four times over, but little better than a good garden-mould. Such plans, 

 moreover, all violate one of the most important of sanitary laws, which is 

 that all refuse matters which are liable to become injurious to health 

 should be removed instantly and be dealt with afterwards. With all 

 these plans it is an obvious advantage on the score of economy to keep 

 the refuse about the premises as long as possible ; and the use of deodorants 

 of various sorts, or even of disinfectants, proves that this is the case, and that 

 these systems all depend upon a fallacious principle. They should therefore 

 be discouraged as much as possible, and only resorted to as temporary expe- 

 dients, or with small populations under exceptional circumstances. 



II. The water-carriage system, on the other hand, is based upon a sound 

 principle, that of removing all the refuse matters at once, and in the cheapest 

 possible manner, by gravitation, and ought to be resorted to in all but the 

 most exceptional cases. 



The opinion of the Committee, that all sewers should be made of impervious 

 materials, and that separate drains to dry the subsoil should be constructed 

 where necessary, has already been most emphatically expressed. 



The freest possible ventilation of sewers, house- drains, and soil-pipes, in 

 order to prevent accumulations of foul air, is also essential. 



With regard to the utilization of sewage, the Committee has come to the 

 conclusion that the precipitation-processes that it has examined are all in- 



1873. 2 G 



