SEWAGE AND SEWAGE RIVERS. 167 



attention. Mr. Calvert has proposed it also for the Medlock, 

 as I am told, with the addition of some original, and I do not 

 doubt valuable, plans for collecting the precipitate without 

 interrupting the flow of the stream. 



The inquiry into the plan proposed by Mr. Higgs, to have 

 a reservoir at Bermondsey, in which he would precipitate the 

 sewage by lime, gave rise to some points for consideration, 

 which may be mentioned. 



It was stated that the phosphates would precipitate, and 

 that this would take place in about six hours. 



It was also said that the sulphuretted hydrogen would be 

 thrown down by lime. 



The ammonia would be lost entirely, except such as might 

 be formed from the solid organic matter containing nitrogen, 

 and found in the precipitate ; of course, all tliat came from 

 urine, which gives the greatest portion, was lost. 



There was another objection, as this precipitate was to be 

 dried, and in that case the lime would prevent the preserva- 

 tion of the portion of the ammonia left in the solid, at least 

 to a great extent, entirely removing the other portion. 



The sulphuretted hydrogen was not quite removed, as was 

 admitted, but it was proposed to be burnt by passing it 

 through the fire. The same thing was to be done with the 

 remaining organic substance which caused the residual smell 

 after the lime had done its utmost towards deodorizing. This 

 plan of burning gases, by passing them over fire or through 

 hot chimnies, is by no means an efficient one, unless the gases 

 be small in quantity and the fire long. I have seen it more 

 than once quite fail. The escaping ammonia was to be re- 

 tained by means of muriatic acid, which would unite with it 

 meeting in the flue. This is a plan attended with difficulties, 

 unless the flue has very little draught in it. On the whole, 

 then, lime does not seem desirable, because it does not quite 

 destroy the sulphurretted hydrogen, and does not retain the 

 ammonia; otherwise I must allow that it is really a beau- 



