88 Notes 011 the Auriferous Slate ^ Granite Veins of N.S.W. 



the dams were all filled in tlie space of thirty hours, when it 

 began again pouring into the sea. The weir at Botany is 101 

 inches in width, and the depth of water now passing over it is 

 five inches. In conclusion, I would observe that I have, I think, 

 shewn beyond a doubt that the water which falls upon the 

 Botany catchment, if properly conserved, is capable of supplying 

 Sydney, and the whole of the suburbs with a minimum quantity 

 of twelve millions of gallons per diem for any number of years 

 to come ; that it will suffice until the present population (taking 

 it at 120,000) increases to 480,000 ; and that the recommendation 

 of the Water Commission to abandon it is absurd. At the same 

 time, I would recommend that no means should be left untried 

 of determining on the best source from which an auxiliary 

 supply may be had, so that when required it may be brought 

 into operation. I would therefore strongly urge that the 

 Botany watershed should never be abandoned as the main source 

 of the supply to these municipalities ; that no trespass should 

 be allowed on the watershed which can in any way decrease the 

 quantity or affect the purity of its water, which stands unrivalled 

 for its excellence. 



Art. IV. — Notes on the Auriferous Slate and Granite Veins of 

 New South Wales, hy H. A. Thomson, Ssq. 



[EeacT before the Society, Nov. 2nd, 1870.] 



In a paper on the " Formation of mineral veins, and the deposit 

 of metallic ores and metals in them," published in " The 

 Transactions of the Eoyal Society of Victoria, for 1867," the 

 writer discussed the different views advanced to explain these 

 phenomena, and pointed out what appeared to be the only theory 

 which would account for the facts observed. 



It is now proposed to lay before the Eoyal Society of New 

 South "Wales a short description of auriferous slate and granite 

 bands of rock occurring in this colony, and as the conditions 

 under which the gold is found in situ in the slate and granite 

 appear to strongly support the views previously advanced, it 

 will be necessary to restate the conclusions then arrived at. 



