1865.] Hull on Water Supply from New Red Sandstone. 419 



ation ; the brooks have been turned, into pestiferous sewers — the wells 

 have either dried up or become poisonous ; — and the evil through 

 generations of neglect has reached such gigantic proportions, that 

 even Parliament refuses to deal with it. 



Private companies, also, which have heretofore been depending to 

 some extent on neighbouring streams, are now forced to extend the 

 bounds of their area of collection to greater distances, or to sink 

 wells, where the geological structure of the district will admit of them, 

 to great depths, and apply powerful machinery. The Birmingham 

 Water Company is a case in point. Hitherto the company have been 

 deriving their supply from the brooks and wells, but this year they have 

 found it necessary to come before Parliament and ask for powers to 

 enable them to extend their area of collection. In his evidence, Mr. 

 Hawksley, the consulting engineer of the company, stated that they 

 were making provision, by the sinking of additional wells, for ultimately 

 abandoning one of their present sources of supply — the tributaries of 

 the river Tame, which there was every prospect would become unfit 

 for drinking purposes, owing to the spread of buildings and factories 

 in the neighbourhood. 



Happily for the prosperity of our great towns, Nature offers a 

 remedy for some of the evils alluded to : our country possesses its 

 mountain ranges on the one hand, and wide-spreading tracts of water- 

 bearing formations on the other, and there are few towns of importance, 

 at least in the Central and Northen Counties, which are inaccessible 

 to one or other of these sources of water-supply. In the one case, the 

 mountains receive the rainfall on a surface nearly free from hurtful 

 impurities, and thence it is formed into brooks and lakes ; in the 

 other, the rocks gather and imbibe a portion of the rains, and retain 

 it until raised again to the surface by mechanical appliances. 



Of the several water-bearing formations of England, the Chalk 

 and the New Eed Sandstone are by far the most important, the former 

 occupying parts of the South and East of the country ; the latter 

 parts of the Midland and Northern Counties ; with this we are only 

 here concerned, except that we may remark that of the two formations 

 the Chalk occupies by much the largest area ; while from its situation 

 it receives proportionately less rain on its surface than the New Eed 

 Sandstone, so that the actual quantities imbibed by each, ceteris 

 paribus, may not be very different. In each case the formation is 

 homogeneous ; is of considerable thickness ; occupies large areas of 

 country, and is easily permeable to water. These are the essential 

 qualities of all water-bearing formations of any pretensions. 



Confining our attention to the New Eed Sandstone (or lowest divi- 

 sion of the Trias), we shall notice in order the above characteristics 

 upon which its capacity for retaining and yielding large quantities of 

 water depends. 



And first as regards its homogeneity, or uniformity of mineral 

 composition (we use the term merely as it applies to our present 

 inquiry), there are doubtless different members, some slightly harder 

 and less porous than others, but the whole formation is essentially a 

 sandstone or conglomerate, rarely containing bands of clay or shale, 

 and hence, whatever water falls on its surface, finds no barrier to its 



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