12 



SEWAGE AND ITS PURIFICATION 



(b) Slop water, containing urine, soap, and the dirt from the 

 surface of the body and from clothes. 



(c) Liquid refuse and drainage from stables, cowsheds, pig- 

 geries, and slaughter-houses (the drainage from stables is very 

 rich in urine ; one horse excretes about fifteen times as much 

 urine as an adult man). 



(d) Street washings and sweepings. 



{e) Urine and water from public urinals, and usually from a 

 few water-closets. 



(/) Waste liquors from factories. 



(g) Drainage of land, rain and storm water, except where the 

 " separate system " of sewage, which excludes these, is adopted. 



The average figures for the sewage for midden and water- 

 closet towns, as given by the Rivers Pollution Commissioners, 

 show no very conspicuous difference in composition, while 

 according to Sir E. Frankland in earth-closet localities a 

 similar uniformity was observed. 



Parts per 100,000. 



Water closets were first introduced in 1810. In towns on 

 this system the inclusion of solid excreta is balanced by the water 

 used for their carriage, the result being that the two sewages 

 are practically equal as regards subsequent disposal. At Oldham 

 in 1900 over 3,600 pan closets were converted to the water- 

 carriage system, and the effect on the town sewage is shown by 

 the following analyses in parts per 100,000 : 



