118 On Artesian or Overflowing Wells. 



It is not unfrequent, again, to cut across several veins of water 

 with one boring-shaft. This was the case in a well at the 

 brewery of Messrs Liptrap and Smith, a mile east of London, 

 where, partly by digging, partly by boring, a depth of 370 feet 

 was reached. The first spring was found above the London 

 clay, the three following under it in the plastic clay, and the 

 last in the limestone, 123 feet below its upper margin. The 

 springs which rose from the plastic clay, all ascended to the 

 same height, namely, to high water-mark on the Thames, which 

 is there 36 feet under the surface of the surrounding country. — 

 (Conyleare, n. a. p. 45.) * Likewise, in sinking a well in St 

 Owen (as mentioned in the Globe, No. 54, for this year), five 

 different veins of water were intersected. 



Of the last case, M. Hericart de Thury mentions the curious 

 circumstance, that an already existing Artesian well, in the vi- 

 cinity of which the new one was sunk, was not at all affected by 

 it+. Both together yield about 700 cubic yards of water in 

 24 hours. A similar case, where two adjoining springs do not 

 appear to have disturbed one another, is mentioned by the same 

 author, in the Annal. de VIndustrie, t. ii. p. 63. At Epinay, 

 near St Denis, in one of the highest points of the park of the 

 Countess Grollier, 16-5 yards above the mean level of the 

 Seine, two wells were bored at the distance of a yard from one 

 another, each of which yielded from 85 to 40 cubic yards, or 

 from 38 to 39,000 Hires of water in 24 hours. The source of 

 the first was at a depth of 54-4 yards, and its surface remained 

 4-55 yards under the surface of the ground. The same was 

 the case with the second, , when it was sunk to an equal depth ; 

 but after the boring was carried to 67*3 yards, the water rose 

 0-33 yards above the surface of the ground. In London, phe- 

 nomena have even occurred that indicate very distant wells to 

 stand in a certain connexion with one another. Neither is it 

 striking, that on the sea seast, where ordinary springs are often 

 regulated by the ebb and flow of the sea, wells of this descrip- 



* The water thus in no way rose 30 feet above the surface of the ground, 

 as stated in the appendix to the German translation of Gamier 's work. 



+ It is not strange that, as was here the case, the boring-iron was strong- 

 ly magnetic. Even rods of iron at rest, in a perpendicular position, become 

 magnetic ; how mucli more must it be the case in an operation, when, in this 

 position, it is subjected to violent shocks ? This magnetic property of the 

 boring-iron is a very common appearance. 



