ON THE CIRCULATION OF UNDERGROUND WATERS. 405 



Bath is supplied with water by no less than eighteen private compa- • 

 nies ; the chief quantity of water is derived from springs off the Upper 

 Lias. The water derived from the Beacon springs is described as the best 

 by the Royal Commissioners ; but even this is not quite satisfactory, and it 

 is a remarkable fact, pointed out by them, that the thermal springs of Bath, 

 like the cold water, contain a large amount of organic impurity (see table, 

 p. 404). J-^ 



These waters have been tapped in a well at Kingsmead Street, at the 

 junction of the Keuper and Penarth beds. They were believed by William 

 Smith, and later by Sir Charles Lyell, to rise from subjacent carboniferous 

 rocks at a great depth. They give off, according to Dr. Daubeny, a 

 daily quantity of 250 cubic ft. of nitrogen gas as well as carbonic acid gas. 

 Lithium, strontium, and copper have been determined in their waters by 

 Dr. Roscoe, and the following salts were found by Messrs. G. Merck and 

 Galloway in an imperial gallon : — 



Carbonate of lime 8*820 



„ magnesia 0-329 



„ iron 1071 



Sulphate of lime 80-052 



„ potassa .., 4-641 



,, sodium 19-229 



Chloride of sodium 12-642 



„ magnesium 14-581 



Silicic acid 2982 



The following well sections, collected by Mr. Bristow, F.R.S., in the 

 Bath district will be found useful for thicknesses : — 



1. America Buildings, near Lansdown. 



Feet. 



Fuller's earth 20 



Inferior Oolite 30 



Midford sand 100 



Blue clay (Lias) 24 



174 



Water obtained. 



2. Beckford's Tower. 



Feet.. 



Great Oolite 30 



Fuller's earth .; 70 1 



Sand 



lOGt 



3. Claverton Down. 



Feet. 



(Great Oolite) . Bastard freestone 80 



(Fuller's earth). Clay 20 



100 

 Water obtained. 



4. Holloway Brewery, above the Old Bridge. 



Feet, 



Midford sands. Rotten sands 30 



Lias. Blue clay with whinstone hands 200 



230 

 Well abandoned, no water. 



