ACTIVATED SLUDGE PROCESS. 215 



Furthermore, the pavement on the street may be influenced 

 by: — Improper raking; allowing mixture to get too cold; smooth 

 foundation; improper type of roller, etc., assuming binder and 

 foundation are perfect. 



I am aware that this looks like a formidable array of 

 obstacles, but you will observe that it is not leally so, as most of 

 the conditions enumerated are settled previous to the work by the 

 engineer in charge or the chemist. The point I wish to make is- 

 that if you want something good you must pay for it ; you cannot 

 get anything good either for nothing or cheap ; and eternal 

 vigilance is necessary in making an asphalt pavement as it is the 

 price of success. 



Furthermore, I wish to emphasise the point that highway 

 engineering has passed beyond the happy-go-lucky, hit-or-miss. 

 rule-of -thumb methods, and become one of the arts that is of 

 .sufficient importance to endow Chairs in Universities. 



PURIFICATION OF SEWAGE BY THE ACTIVATED 

 SLUDGE PROCESS. 



BY 



Reg. J. Morris, A.M.I.S.E., M.R.San. I. 

 Borough Engineer' & Office, Kingwilliamstown. 



Fend Juh/ 12, 1921. 



The purification of sewage has always been a knotty problem 

 which engineers and chemists have had to grapple with. Every 

 town naturally desires to keep itself sweet and clean and to dis- 

 charge its sewage outside. The people outside naturally do not 

 desire it in their midst for several reasons. It is not only 



unsightly, but has an obnoxious odour and the disposal takes 

 up much land. The city or town overcomes some of these diffi- 

 culties by purchasing a good-sized plot of land for the sewage 

 treatment and endeavours to render the sewage as innocuous as 

 possible by scientific treatment. 



It has long been felt, however, that the last word has by 

 no means been said in the direction of scientific sewage disposal, 

 and municipal authorities have been waiting for a system of 

 dealing with sewage which would entail less capital cost, which 

 would require less land, and would make the sewage a remunera- 

 tive by-product when it was disposed of. 



The Activated Sludge Process claims to fulfil all these require- 

 ments and to have revolutionised the treatment of sewage 

 disposal. 



Messrs. Jones and Attwood, Ltd., of Stourbridge, England, 

 the makers and patentees of the Activated Sludge Plants, claim 

 the following advantages : — 



(1) Ideal purification can be obtained with absence of all 

 aerial nuisance. 



