WATEIt SUPPLY TO SYDNEY BY GEAVITATION. ,115 



tapping the open channel from behind Mount Keira, when this 

 canal, if made, would necessarily pass quite close to the top of 

 the cliffs at Eixon's Pass, or gap behind "Wonona and Bellambi, 

 and which Pass is about 1,160 feet over the sea ; from thence it 

 is about seven miles to Smith's Hill at Wollongong, where I 

 found that hill was 130 feet over the sea. From the main 

 channel, on the top of the mountain at Eixon's Pass, a small 

 wrought-iron pipe might be laid to connect with a receiving 

 and distributing reservoir on the apex of Smith's Hill, which 

 would command the whole of the town of Wollongong for 

 reticulation of service pipes. The plan is so simple that it would 

 resolve itself only into a question of expense for the supply of 

 that town and suburbs, should it become sufficiently important 

 under proposed railway development. 



With such head of water on to Smith's Hill, reckoned at 1,000 

 feet, the delivery by a 9-inch pipe in wrought iron would be 

 no less than 1,497,210 gallons each twenty-four hours, or say 

 1,500,000 gallons of purest water, which would probably be 

 more than a week's supply for the town of Wollongong, whilst at 

 the same time the release of the hydraulic pressure of so much, 

 water deliverable in twenty-four hours into the distributing- 

 reservoir on Smith's Hill would afford the townspeople there no 

 less than 315 horse-power available for local industrial factories 

 for constant day and nigl>t use as long as the water w T as on. Of 

 course a very much smaller pipe and supply would suffice for 

 Wollongong as it is; but I give the working of a 9-inch pipe, 

 in order to show the effect and what could be done for the place 

 by these measures under such advantages, always provided that 

 the main supply in the aqueduct above was made equal to such 

 extra demand upon the general consumption ; and which certainly 

 could be ensured in all seasons by tunnelling under the old Mount 

 Keira Boad, and continuing the main channel further and further 

 south along the western slopes of the rising coast range, which 

 gradually rises up to 1,745 behind Kiama, and to 2,000 at the 

 extreme south part of the great coal basin, some 6 miles further 

 on towards Broughton's Creek and Shoalhaven. 



In my former paper I touched upon the great importance of 

 coating the inside of the wrought iron pipes in such a manner as 

 to ensure them against corrosion. I desire to repeat this remark, 

 lest I might by some be considered to have overlooked this point. 

 In Nevada this is done by immersion of the pipes into a mixture 

 of boiling asphalt and coal tar ; but the great importance of 

 making the inner wall of the main perfectly safe against corrosion, 

 and freed from all risk of a coal-tarry taste to the waters, would 

 seem to warrant the adoption of a comparatively dearer though 

 cheap system of enamelling by the use of certain resins dissolved 

 in cheap methyllated spirit to be applied and to be burnt on the 



