Section I. 

 SANITARY SCIENCE AND HYGIENE. 



1.— SOME NOTES ON THE BIOLOGICAL TREATMENT OF 

 SEWAGE, WITH SPECIAL REFERENCE TO THE WORK- 

 ING OF SEVERAL INSTALLATIONS AT NORTH SYDNEY. 



By EDWARD 8. STOKES, M.B., Ch.M., D.P.H., Medical Officer and Bacterio- 

 logist to the Metropolitan Board of Water Supply and Sewerage, Sydney, New 

 South Wales. 



[With Plate.] 



The treatment of sewage has now become an ever-present problem 

 with us in this continent, and in the future it will with certainty call 

 for determination with increasing emphasis. Obviously the reasons 

 for this are intimately connected with the growth of our towns and 

 cities, with the concomitant advance of ideas embraced in the progTes- 

 sive civilisation of the age, and with the more widely spread recognition 

 of the truth of the hygienic principle that accumulation of refuse and 

 waste-products in and around our dwellings make for disease and 

 disaster. 



That the solution of the problem is beset with difficulties must be 

 evident to everyone who dwells seriously upon it ; but in this connection 

 it is interesting to note that it is not uncommon to encounter indi- 

 viduals who, although they should know better, will readily settle 

 the point by advising everyone rec[uiring information to go and build 

 a septic tank and the microbes will do the rest. 



The history of sewage treatment is full of interest, as exemplifying 

 the peculiar complexity of the subject. Whilst it would be beyond 

 the scope of this communication to traverse the past, I might be per- 

 mitted to state that during the past 50 years in England commissions 

 dealing directly and indirectly with inquiries into the treatment of 

 sewage have been sitting for more than 25 of such years, and that at 

 the present time the latest Commission, appointed in 1898, is still in 

 existence — full of vigor, and with no indication of the advance of old 

 age. The significance of these facts is apparent. 



Although the last word on the subject is still far ahead of us, yet 

 we may consider we have reached a point at which we can venture, 

 without being dogmatic, to present certain soundly established prin- 

 ciples underlying the biological treatment of sewage. 



