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WATER SUPPLY IN THE CARLISLE BASIN. 



By T. V. HOLMES, F.G.S. 



I HAVE nothing to say in this paper about water supply in 

 connection with the rivers and brooks of this district, the quantity 

 and quality of their waters. In these days of the rapid increase 

 of population and manufacturing industry, it is well that each 

 important town should have its attention called to any means of 

 procuring a supply of pure water which the geological structure of 

 the neighbourhood may afford, apart from its streams. And the 

 letter of a writer in the Carlisle Journal, of March 23rd, mentioning 

 the existence of a salt spring at Kelsick Moss, and asking its cause, 

 inclined me to think, while writing a brief reply, that this water 

 question is well fitted to be the subject of a short paper on this 

 occasion. 



Having elsewhere described the rocks of the Carlisle Basin,* 

 I will here treat of their nature and arrangement only so far as the 

 subject now before us requires. These rocks, as regards water- 

 supply, primarily divide themselves into two distinct groups ; the 

 superficial beds, consisting of glacial drift, peat, and alluvium, which 

 cover the surface, and the Permian, Triassic, and Liassic rocks 

 beneath them. The arrangement and distribution of these two 

 groups are perfectly distinct, the underlying rocks having definitely 

 restricted areas, while the glacial drift and other superficial beds 



* Quart. Journ. Geol. Soc. 1881 ; Proc. Geol. Assoc. Vol. VII., No. 7 ; 



Trans. Cumb. Assoc. Part VI. 



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