8o VREDENBURG : RECENT ARTESIAN EXPERIMENTS IN INDIA. 



sandstone four inches thick has been met with at a depth of 344 

 feet, and a second one 2 feet 2\ inches thick, at a depth of 359 feet. 

 In a letter dated 19th November 1892, addressed to the Government 

 of Madras, Dr. King recommended that the boring be carried down 

 to a depth of at least 450 feet. 



Rocks of upper Gondwana age are found also near the mouths 

 oi the Godavari, and they have yielded water 



Boring at Ellore. . . .... 



at rLllore in a boring which is still in progress 

 at the present time. The strata dip towards the sea-coast to the 

 south-east, in which direction they sink beneath volcanic rocks, of 

 the age of the " Deccan Trap, " Rajahmundry beds of the age of 

 the Cuddalore sandstones, and finally alluvium. The'upper Gond- 

 wanas here consist principally of sandstones, an upper series, 

 the Tripety sandstones, and a lower one, the Golapilly beds. A series 

 consisting principally of clays, the Kagavapuram shales, intervene 

 between the two sandstone groups. It has no great thickness but 

 from its impermeable nature it provides a confining stratum to the 

 water contained in the Golapilly sandstone, the other requisites 

 for artesian action being provided by the lie of the stratification. 1 

 It is difficult to decide, without having seen any specimens, how 

 much of the alternating sands and clays met with up to a consider- 

 able depth in the Ellore boring may belong to the alluvium, to the 

 Rajahmundry beds or to the Tripety sandstones. Some specimens 

 from a depth of 367 feet were forwarded to the Geological Survey. 

 Office and examined by Mr. Holland who identified them as pro- 

 bably belonging to the Ragavapuram shales. The circumstances 

 therefore seemed favourable, on account of the probable proximity 

 of the underlying Golapilly sands. In a letter, dated 13th June 1900, 

 Mr. Holland had just expressed his opinion as to the advisability of 

 continuing the boring, when a communication forwarded on the same 



1 The geology of this country has been described by Dr. King in his paper on " the 

 upper Gondwanas and other formations of the coastal region of the Godavari district." 

 Mem. Geol. Surv. Ind., Vol. XVI, p. 195. 

 ( 80 ) 



