ON THE CIRCULATION OF UNDERGROUND WATERS. 117 



ill the Greensand area of the Haldons, runs through the Combe valley above 

 Teignmouth, a large part of the water being received in a small reservoir for 

 the supply of that toAvn ; the remaining portion of the water left in the 

 Btream, after flowing down the natural channel, is conveyed in a culvert 

 thi-ough the grounds of Myln Villa, after which it flows to the river Teign. 

 During the severe drought of 1870 nearly the entire supply of this stream 

 was taken by the reservoir, and only twenty gallons of water jDer minute 

 entered the high end of the culvert at Myln Villa ; but notwithstanding that, 

 no less than fifty gallons per minute were discharged. Wells were sank to 

 secure more of this excess supply, which was found. 



Tiverton. — At Tiverton Mr. H. S. GiU informs Mr. Pengelly that the 

 surface of the water in the wells at the Parish Church and of St. Peter Street 

 is 10 feet below the level of the ground, while at the other end of the street, 

 which is at a slightly lower level, the water has to be pumped up 35 to 40 

 feet, and of much harder quality than that derived from the shallow wells, 

 which are, however, affected by heavy rains, during which the deeper well- 

 water remains clear and sparkling, especially in a weU near the Town Hall, 

 about 270 feet above the sea. 



Daivlish. — Dr. Baker informs Mr. Pengelly that the springs are believed 

 to trend with the valley N.N.W. and S.S.E. ; breaking at right angles to this 

 line, the wells have to be sunk to a level a little below that of the sea. 



A well at Captain Lampen's on the North Hill, 171 feet above the sea- 

 level, was sunk 175 feet through sandstone, gravel, and sand rock, of which 

 100 feet had to be penetrated before water was found. 



In a well (Mr. Turner's) 50 feet lower down the hUl, 73 feet deep, the 

 water suddenly disappeared in March 1875 ; but some water was reached on 

 sinking an additional 5 feet. 



In Mr. Marshall's well, recently sunk close to the edge of the cliif, on the 

 opposite side of the valley, at a height of 70 feet above the sea-level, water 

 was reached at 75 feet, beneath a hard pan of red sandstone ; when pumped 

 dry, five minutes' rest yields sufficient for thirty minutes more pumping. 



At Oaklands, on the S.W. hill, a well is now being sunk at an elevation of 

 200 feet ; a surface-spring was met with at 42 feet, which has been cut off, 

 and the well is now in hard conglomerate at 65 feet. 



Near the Station, Hatchers Hotel, and along the railway, an abundant 

 supply of surface-water is found in the gravel at a depth of 14 feet, which 

 supply appears to be pounded back by the sea ; these surface-springs vary much 

 in quantity, and are lowest in July. The wells are bricked, and 3 feet 9 inches 

 diameter. 



Bramford Speke. — Mr. Gamlen, of Bramford Speke, near Exeter, informs 

 Mr. Pengelly that there are 16 wells in that village, of which 14 are from 

 45 to 52 feet in depth ; the top water of one of these is maintained to a level 

 only 14 feet below the surface of the ground, rising to within 6 feet 

 in winter. The wells are in fine orange- coloured sandstone, overlaid by clean 

 gravel ; the bottoms of the wells are below the level of the Exe, but the water 

 is derived from the high ground to the west. 



Somersetshire. 



At Taunton Mr. Moore reports the deeper weUs 75 feet in depth, situated 

 100 feet above the sea ; Dr. Alford states these are with difficulty jjumped dry ; 

 the water is derived from the New Eed Sandstone, and contains 6 grains per 

 gallon of sulphate and carbonate of Ume. 



