ABSTRACT OF PROCEEDINGS. XCV. 



coarse sand, fine gravel and broken rock, preferably lime- 

 stone. In the water supply of Buenos Ayres it had been 

 found that the introduction of a layer of cinders in the filter 

 produced a brilliantly pellucid water, and the albuminoid 

 ammonia was reduced from 0*24 part per million in the raw 

 water to 0*01 part per million in the filtrate. He alluded 

 to experiments now being carried out in Brisbane for the 

 destruction of algae by the use of copper sulphate, where 

 it is found that the result is not so satisfactory with the 

 soft water which obtains there as with the harder waters 

 in America. 



Mr. J. Haydon Cardew, Assoc m. inst. c.E. in moving a vote of 

 thanks to the author of the paper, said that although filtra- 

 tion of water was fully understood and successfully practised 

 in Europe and America it had been almost entirely neglected 

 in Australia. The Sydney water supply although it is 

 gathered on an area which, geologically considered, is 

 extremely favourable to purity, is exposed to many dangers 

 from the character of the settlement on its surface, and it 

 was a question worthy of the consideration of the authorities 

 whether filtration should not be adopted if only as a pre- 

 cautionary measure. In country towns water supplies in 

 this State the question was one of even greater urgency, 

 because it was well known that there were only a very few 

 that supplied water fit for human consumption, and that if 

 the quality of the water was tested by the rules and con- 

 ditions laid down in the paper, the majority of the country 

 water supplies of the State would be absolutely condemned. 

 In this country, probably due to climatic conditions, there 

 is generally an abnormal development in all storage 

 reservoirs of animal and plant life ; in one reservoir myriads 

 of small green frogs swarmed to such an extent as to block 

 the pipes, and although the gathering ground was of granitic 

 formation, only devoted to grazing cattle and remarkably 



