BY THK HON. W. F. TAYLOR, M.L.C. 



27 



With regard to our immediate smTouudiugs, the Brisbane 

 River, below Ipswich, is a non-potable stream — the water not 

 being used for any domestic purpose beyond watering the streets 

 and for swimming baths ; and up to the present time all the 

 contaminated water of the city and towns on its banks has been 

 allowed to flow into it. What has been the effect of this on the 

 health of the peopla residing on or near the river banks .' This 

 is a matter that should be very carefully and seriously considered, 

 for if no evil effects have followed so far, it is clear that the river 

 is sufficient m size to purify by oxidation the sewage which has 

 been admitted into it ; and if that is the case the question arises, 

 " Is it not capable of dealing also with the material at present 

 intercepted •?" The consideration of this matter should be 

 divested of all sentiment, and the question approached in a 

 practical manner, for if all the refuse can be safely admitted 

 into the river without any preliminary treatment, then the 

 difficulty of dealing with the subject of sewage disposal is very 

 much simplified. But if it is found unsafe to health, or 

 Likely to cause a nuisance, to admit the whole of the refuse 

 matter into the river, the sewage could undergo such prelimi- 

 nary treatment as would render the effluent practically harmless. 

 A modified chemical treatment would no doubt answer probably 

 better than filtration or irrigation, as the area of ground required 

 at the outfall would be so small as to render it possible to treat 

 the sewage at a number of different points, to which it could 

 flow by gravitation, thus avoiding the expense of raising it by 

 pumping or pneumatic ejectors, in order to collect it at one 

 point. Chiswick offers an example of the chemical treatment of 

 sewage, the effiuent being rendered sufficiently pure to permit of 

 its discharge direct from the settling- tanks into the River Thames 

 above London. Lime and Spence's alumino-ferric are the 

 chemicals used, in the proportion of seven grains of the former 

 to five grains of the latter to the gallon. The lime is first mixed 

 with the sewage, which then has a run of 300 feet before being 

 mixed with the alum. It then flows into tanks and is allowed 

 to precipitate for three hours, when the effiuent is run off' into 

 the river. The sludge is turned into a small tank at the rear of 

 the sludge-press shed, and is then passed through a Johnson's 

 pneumatic sludge-press, which turns out twenty-four cakes of 



