110 WATER SUPPLY TO SYDNEY BY GBAYITATION. 



same way that the Eureka Water Company in California have 

 successfully constructed their race or aqueduct of 250 miles, at 

 a cost of £180,000. 



It might be thought, from my present advocacy of the high- 

 level scheme, and from my notes on the face of my map, for the 

 low-level plan from Port Hacking Creek, that I quite abandon 

 the lower for the higher delivery (or gathering) method. It is quite 

 impossible that I should not think much more highly of the one 

 than of the other, after the extraordinary relative results proved 

 and exemplified here by Eitelwein's formula for calculating water 

 delivery and water power. 



In advocating the superior high-level scheme, I do not at all 

 abandon the low-level proposals from Hacking Creek — of itself it 

 would have been a grand boon for Sydney, had we not discovered 

 the incomparably greater advantages of the high-gathering plan. 

 I believe that Sydney might have another full supply by gravi- 

 tation from Hacking Creek alone, by aid of the overflow waters 

 at the intake of the high mains, after those mains were constantly 

 and fully charged, when the spare waters could come on by nat- 

 ural gravitation to the lower levels of Port Hacking Creek, and 

 on to my proposed cement concrete dam in that valley. The time 

 may come when the waters of Port Hacking Creek may be re- 

 quired ; the waters to a large extent will be there whenever wan- 

 ted, and it will then be only a matter of counting the cost of send- 

 ing such extra supplies by slow gravitation into the lower levels 

 of Sydney and about Botany for household purposes, when a 

 large manufacturing population may spring up there. 



It is not for me to project any details of the mode of working 

 my scheme. It is enough that I should give particulars as I have 

 done of the origination of, and proofs of, the value of my discov- 

 ery. I may be asked what would be the expenses of the scheme ? 

 My reply would be that I cannot tell nor could I say what would 

 be the cost of the mains even if we knew what size of pipes would 

 be adopted in the first instance. But this much I would broadly 

 say, in reply to any such questions, that if it pays populations in 

 Nevada to supply their towns and country with water, and with 

 hydraulic force, from high mountains, and by long distances by gra- 

 vitation, and by wrought iron mains especially, so should it answer 

 our purposes to supply our city and suburbs with abundance of 

 pure mountain waters, exclusively from a sandstone formation, by 

 direct gravitation, and more particularly when the water could 

 be made at the same time to yield mechanical force almost 

 equal to the industrial steam-engine power of the population of 

 Sydney. 



I would therefore decline to attempt to make an estimate of 

 the expenses of my scheme ; whilst at the same time I will urge 



