STDITET "WATEE STJPPLT BY GEAVITATION. 47 



present extraordinary advantages for forming a fine dam across 

 a very narrow gorge in this mountain valley, and where there is 

 such an extent of level ground up the river that a proposed 

 dam of 35 feet in solid concrete would render the most effective 

 service, in throwing back an extraordinary amount of further 

 storage waters, which, together with the upper waters, would bid 

 defiance to all exhaustion from every cause. By my proposed water 

 supply scheme, I do not pretend to supply waters for irrigation, 

 beyond supplying gardens abundantly. In my opinion, no system 

 of irrigation can be safely depended upon, unless where canals 

 can be fed from large rivers or proximate mountain streams, 

 which are more or less fed by melting snows, and where iron mains 

 can be dispensed with. 



And now allow me to say a little as to the quality of these 

 waters in the sandstone country. Th-ey are of the purest kind, 

 perhaps unsurpassable even by the waters of Loch Katrin, 

 which supply Glasgow so satisfactorily, and which emanate from 

 a granite country entirely. The sandstones overlying our coal for- 

 mations in that high region are about 800 to 900 feet over the coal 

 seams, and are free from all coaly and other shales. In my survey 

 I observed no departure from the one uniform sandstone forma- 

 tion, and quite free, as far as I could see, from those occasional 

 dykes of trap rock which are to be found in this formation 

 nearer the ironstone ore seams which overlie the coal seams at 

 some 500 to 600 feet, and which might, if present, tend to dis- 

 colour and to make the waters hard and impure. But I saw 

 nothing of this in the Madden's Plains region ; and, for the sake 

 of practical evidence of their brightness, I would inform this 

 Society of a little crucial test I adopted on these waters. I was 

 so struck with their extraordinary clearness in all the running 

 creeks of that region that I tried the effect of tying a coin to a 

 long piece of thread, and lowered it into a waterhole, 5 feet 6 

 inches deep. The day was clear, the coin at the bottom of the 

 waterhole was of course magnified by being seen through the 

 medium of water, and it was illusively thrown forward a long way 

 by the angle of refraction, but when settled at the bottom the 

 stamp impressions continued to be as clear to the eye as if it 

 were on the surface. 



These waters, from coming in contact with nothing but clean 

 and filtering sandstones, are perfectly free from all hardness for 

 washing or for household purposes. It was estimated some time 

 ago in London, that if the waters brought to that city from the 

 calcareous country around were as -free from hardness as the 

 Grlasgow waters obtained from the granite country, there would 

 be an annual saving to the Londoners of £250,000 worth of soda 

 and soap extravagantly lavished there every year beyond the 

 relative proportions of same diturents used in Glasgow. 



