68 report — 1877. 



surface, is, as I reckon it, about 16 feet 6 inches above O.D. It is evident 

 tbe river governs the height to which the water rises. It is stated not to be 

 perceptibly affected by the seasons. 



Ormslcirh Local Board Well. — This is a well lying out of the special area 

 I have marked out for further investigation. It is remarkable as being 

 affected by local rains within 24 hours. The water-level is stated to vary 

 slightly in summer and winter, but has not diminished during the last 10 

 years. The water is pronounced to be remarkably good and soft. There is 

 a very large fault on the west side of the well. 



Borings through the New' Bed Marls. — In two cases I know of, these marls 

 have been pierced ; the one at Alsager within 300 yards of the railway-sta- 

 tion, in which 553 feet of the marls were pierced, and water tapped which 

 rises in an iron tube 10 or 12 feet above the surface. The level of the 

 surface is 310 feet above O.D. The water is very pure and soft, and suitable 

 for brewing-purposes. Though the bore was continued to a depth of 1000 

 feet, the water was not increased thereby. The second case is at Preston 

 Brook, at which the water was tapped after piercing 400 feet of marls. 



An attempt was made to pierce the marls at the Palace Hotel, Birkdale, 

 near Southport, but was given up at a depth of 558 feet. 



I have now recapitulated the leading features of the wells outside of Liver- 

 pool and Birkenhead of which I have information. As the answers are 

 already printed in extenso in the two Reports of the Committee, any one 

 wishing for more detailed information can there obtain it. 



Inferences. — Though the information is any thing but of a scientifically 

 exact character, it appears to me that some useful inferences can be drawn 

 from it. They are these : — 



As to the present Water-level. — It is quite clear that, when a well or a 

 system of wells is established in a district, the permanent water-level is 

 lowered to the extent of the draw upon the supply. Though I call this 

 the permanent water-level, I merely do so to distinguish it from the tem- 

 porary level of water in the well produced by, say, 12 hours' pumping. It 

 is not naturally, but becomes artificially, the permanent water-level of the 

 country ; and in any case, were the pumping-operations to cease entirely, I 

 should expect to see the natural water-level restored in 12 months. 



As to the effect of load Bains. — In only a few instances have the observers 

 stated that they could distinguish the effect of rain on the wells. Even in 

 the one in the drift at Sankey Bridges my informants say they can distinguish 

 no seasonal changes. It is quite possible, however, that this bottom- drift gravel 

 may be supplied from springs in the rock below. The Ormskirk well is a com- 

 paratively shallow one, and the local rains affect it, I should say, by immediate 

 local percolation. It will be seen that the Liverpool wells are not altogether 

 exempt from this local percolation ; at all events the Bootle well is not. This, 

 however, is only in accordance with what we would expect inferentially from 

 a consideration of hydraulic principles ; the larger the area from which the 

 supply of water is drawn, the less likely is the well to be affected by local 

 rains. The nature of the top rock, the dip of the beds, the number and 

 position of the fissures in the rock, the proximity of a fault, will all assist to 

 determine the extent of local percolation. If, however, the well and the bore 

 is made watertight by tubbing and tubing to a considerable depth, local 

 rains cannot influence the yield to any perceptible extent. When a great 

 thickness of clay or marl is penetrated I know of no recorded instance of 

 seasonal variation in the supply from the Triassic rocks. 



