SYDNEY WATER SUPPLY BY GEAVITATION. 43 



George's River on the north and the Loddon and the Cataract 

 Rivers on the south. We continued our course nearly south for 

 some 60 chains, in which short distance we proved (for my pur- . 

 poses) the favourable elevation of 220 feet 6 inches, to the 

 intersection of the road that leads from the Bottleforest Eoad 

 over Madden's Plains to Eice's free selection, which runs from 

 east to west. We then traversed that road west to its junction 

 with Madden's Creek, and continued the survey along the creek 

 by its nearly due west course for a mile and a half from where 

 we intersected the road to where this upper and main source of 

 George's River is precipitated over a deep fall of 55 feet perpen- 

 dicular. In this short distance the levels proved the fact of the 

 advantageous fall of no less than 150 feet 9 inches. 



This sudden rise to the south and sudden dip to the west 

 seemed to me to be at once a convincing proof of the correctness 

 of my preconceived theory, that it must become a very easy 

 matter to lead a large source of water supply to the northward 

 by means of a tunnel that should pierce the high land between 

 the deflections on the south-west of Madden's Plains and the 

 level on the north-west, and from as far back to the south as 

 would be practicable with the required gradients for the full 

 velocity of waters to be conducted through such tunnel. To this 

 end I knew that the south and permanent affluents of Madden's 

 Plains must be close at hand, where they unite into a respectable 

 stream to form the upper source of the Loddon and Cataract 

 Rivers. The survey was continued to those parts, and it imme- 

 diately opened out the grandest results. We came upon the 

 various small affluents of the Loddon River, where they unite at 

 a spot that seemed to be formed for the express use of man to 

 intercept the waters by one easily constructed dam of 46 feet 

 high, that would throw back in times of freshes a lake of water 

 equal to from 1,200 to 1,400 acres, of an average depth exceeding 

 22 feet. This supposed large acreage of water was arrived at by 

 the aneroid and not by the levelling instruments, for reasons 

 I will explain later ; but I may here say that I believe that I 

 rather under-state than over-rate the size of this one magnificent 

 basin, which could be made at a comparatively small expense by 

 means of a dam in concrete, at a most favourable spot, defined and 

 marked out by myself. But not only can this immense reservoir 

 be obtained at t^is grand spot, but there are positions above the 

 back of this one intended dam, applicable for raising other embank- 

 ments on the south side of Madden's Plains, which would give a 

 total of several hundred acres more water. The country where these 

 reservoirs would be is nearly free from timber, and is wholly con- 

 stituted of barren sandstone, covered with coreas, water weeds, 

 epacridae, and such-like scrubby low-growing plants, whilst in the 

 yarious creeks I perceived the evidence of perpetual streams in the 



