18 T. P. ANDERSON STUART. 



acre in use disposes, in a perfectly satisfactory manner, of the 

 sewage from 1,024 persons, and I do not doubt, could deal with 

 the sewage from a very much larger number. And when one says 

 it disposes of the sewage one means absolute destruction, for on 

 analysis the uppermost layers of the soil at the Botany Farm showed 

 an increase in the amount of organic matter after five years con- 

 tinuous use of only "02 'per cent. There is under proper manage- 

 ment, and even with very considerable mismanagement, no chance 

 of any "clogging" with organic matter, and there is no reason why 

 the same soil should not go on doing its work practically for ever. 

 Another consequence of this newer knowledge of the precise 

 manner in which organic matter is destroyed, is to largely remove 

 the question of the disposal of sewage from the domain of the 

 sewerage engineer to that of the biologist, and now one may say 

 that it is the business of the engineer to collect and distribute the 

 sewage, but that it is mainly that of the biologist or of the chemist 

 to say how it should be disposed of or destroyed. I am aware that 

 the engineers do not as yet quite like such an assertion, but it is 

 nevertheless, in my opinion, true. 



These matters have their importance to us now on account of 

 the schemes which had been devised for the sewerage of Parra- 

 matta and Granville. I believe that this scheme might have 

 been much less costly, simply by having the sewage farm much 

 nearer the town, and so avoiding or lessening the cost of pumping 

 and delivery mains. But I look farther ahead than this even, 

 for on the shores of the harbour are plenty of low lying lands, the 

 reclamation of which with suitable material, would at once provide 

 means of disposing of sewage of suburbs, would yield cultivated 

 lands, reclaim unhealthy areas and improve the remaining waters 

 of the harbour. It is true that the great Western Suburbs scheme 

 now in course of construction provides, I believe, most satisfactorily 

 for these suburbs, but there are still other suburbs to be provided 

 for near Sydney, and there are unfortunately numbers of other 

 towns in the Colony still innocent of sewerage arrangements. ~ 



