264 THE PROSPECT AND KENNY HILL SCHEMES. 
approximate only may be inferred from the following remark on 
e lined and unlined construction of the canal :—“ To bring these 
poritart uantities into estimate with exactness is impossible, and 
mately ascertained. These surveys and borings could not be com- 
pleted during the period of my visit.” These estimates seem to 
have been based on the inference that most of the shale which the 
canal line crosses is horizontal, and even bedded, and of an imper- 
meable character, gate the lining of the conduit unnecessary. 
But there is much reason to doubt the correctness of such an 
assumption, as though 1 ina a borehole the shale beds might seem to 
ious, there are good reasons 
for distrusting the evidence of sight, First the shales occur on 
ank of a ridge forming an anticlinal axis, whic: 
exposed, — a most decided i of the — - either side; 
so aa unless lined, on = de exposed to the a some ite 
canal enters this shale at Woodhouse Oreck, at 13 miles from 
starting point in the Nepean River, and will probably ine 
for at least 15 miles. The whole of this distance will prot 
side-walls and £2 per cubic yard for bottom pitching, add 
£391,500 to the above estimate, raising the cost of construction 
of the above works to £1,562, 258. 
Conpurr via Kenny HILt. = 
The character hs the supply conduit for 18} miles, where 
rof the K nny Hill scheme, being idem 
enters the se reservoir of t. enn 
tical with the Plendeck con sails needs no further description: 
From this it consists entirely of cast-iron pipes. ae ‘ 
to conduct the supply from the service reservolr 
two 36-inch pipes, which for the first 691 yards are laid ina tunne 
piercing the dividing range of the Campbelltown hao Nepean 
valley 8, and which about 1, 000 yards further on join os 
rt 
reyeen ‘ilo ok: Sa 
having their valve prot ee the centre of one of the 
eastern valleys of the reservoir, arom ate re 
through a tunnel rds in 
ugh a nel 2,500 yards ayn ioht an pre 
pipeline 
in a north-easterly direction till it joins the perth pe 
from Prospect, 84 miles from Sydney. The country” “engineering 
- 
a 
