Correspondence. 283 



Miner alocjkal Report upon a portion of the Districts of Nettore, Cuddapah, 

 and ' Guntoor. By Lieut. Ouchterlony, F. G. S., Madras Engineers. 



This is a very foil report on the causes of failure that have attended 

 Mr. Ouchterlony's recent attempts to turn the Nellore Copper Mines to 

 good account. We are always sorry to hear of unsuccessful attempts of 

 this nature, although they are often more valuable than more nattering 

 statements of the riches of mines. 



The district which was the scene of Mr. Ouchterlony's enterprise, is 

 bounded to the westward by the Ghauts of Cuddapah, the central mas- 

 ses of which consist of granite. Towards the sea, a broad band of late- 

 rite forms the general line of coast. Mica slate and clay slate, with occa- 

 sional protrusions of granite, greenstone, and basalt, form the principal 

 * portion of these extensive districts. Transition limestone is, however, 

 found on the flanks of some of the higher granite elevations. 



At a place called Agnigundolah, the clay slate is traversed by a huge 

 channel of siliceous rocks, running N. E. and S. W., and dipping almost 

 perpendicularly, the clay slate being on either side much indurated and 

 altered, and its beds to a small extent contorted. In the substance of 

 portions of this quartzose dyke green copper is seen disseminated 

 through the stone in small scanty grains in the form of a silicate, and 

 tinging the walls of the channel and sides of its fissures, with a solution 

 of green carbonate. 



Further than this, no ore whatever is to be seen, and the cold bare 

 appearance of the rocks, very soon satisfied Lieutenant Ouchterlony, 

 " that the search for ore in this locality was not a legitimate mining 

 enterprize." 



In another part of the district, (near Nellore,) composed of mica slate, 

 extensive indications of copper ore occurs, consisting of round pebbles, 

 imbedded in the alluvium, and tinged green with carbonate of copper are 

 seen ; similar green stains are seen on veins of quartz insinuated 

 between layers of greenstone or hornblende slate and mica slate. 

 Trials were made here in various places to a depth of twelve or four- 

 teen fathoms, by Captain Ashton ; but the result invariably proved that 

 the ores were not sufficient to pay the expense of blasting the hard 

 rock, and keeping the mine free from water, which flows with remark- 

 able constancy into the sinkings. 



Attempts were made by Lieutenant Ouchterlony at Sagligherry, 

 Cummuldinna, and other places, where similar indications were observed, 

 with the same unfavourable results. Lieutenant Ouchterlony justly con- 

 demns the reports of Dr. Heyne and others, who held out the most extra- 

 vagant inducements to speculators in the Nellore mines. 



