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may be found almost everywhere, and rest indifferently on any of 

 the underlying rocks. Thus, the Glacial Drift may afford an" 

 equally good supply for the shallow wells of farmhouses, whether 

 the underlying rock is of Carboniferous, Permian, or Liassic age. 

 But water in quantity sufficient to supply a city like Carlisle could 

 only be obtained from wells penetrating not only the Glacial 

 Drift, but more or less of the underlying rocks. And the possi- 

 bility of getting water from these lower beds in any given spot, 

 depends on their nature, arrangement, and distribution. 



The surface of the ground in Cumberland bordering the Solway 

 is most persistently covered with Glacial Drift or other superficial 

 beds, so that the amount of visible rock of Permian, Triassic, or 

 Liassic age is extremely small, and almost confined to the banks 

 or beds of the rivers. Even along the rivers these lower beds may 

 be very slightly exposed, sections in them such as those in the 

 Eden at Wetheral, Shalk Beck above East Curthwaite, or the Lyne 

 above Cliff Bridge, Kirklinton, are very seldom met with. The 

 full thickness of the Glacial Drift is not often shown in railway 

 cuttings. Journeys, for example, from CarUsle to Silloth, Wigton, 

 Wreay, Wetheral, Longtown, or Gretna, take us through cuttings 

 from twenty to thirty feet in depth, but in none of them is anything 

 seen, on the most careful inspection, but superficial sand, gravel, 

 and clay. And though the farms and villages of this part of Cum- 

 berland are almost invariably supplied with water from shallow 

 wells in the Glacial Drift, well-sinkers are very careful to avoid 

 penetrating to the lower rocks, as water attained on getting to a 

 clayey stratum in the Drift might be lost on sinking through it and 

 reaching a porous sandstone below. The Glacial Drift is of very 

 various composition. It usually makes a light rather than a heavy 

 soil, being, on the whole, much more gravelly than clayey. But 

 at various levels seams of clayey material exist, which hold up 

 much of the water falling on the surface as rain, and allow of a 

 great number of shallow wells. Scarcely any rain can fall directly 

 on the underlying rocks, the only considerable space almost or 

 quite free from drift being a piece of country, a Uttle more than a 

 square mile in area, between Aspatria and West Newton. But as 



