650 ME. G. ATTWOOD ON AUEIFEROUS TRACTS OF 



In prospecting for gold in Southern India one feature of especial 

 interest was observed, that is, the general absence of alluvial depo- 

 sits rich in gold ; this and the absence of ancient river-bed gravel 

 containing gold make it evident, after inspecting the auriferous 

 lands of other countries, that the natives have years ago extracted 

 the metal, and they have also tested with care the various outcrops 

 of quartz in their search for gold. The ancients were by no means 

 inferior miners, to judge from the author's experience, as he never 

 found gold in a single place or rock where the old miners had not 

 left indications to show that they had worked before, although 

 several hundred tests were made. 



Therefore where the ancient workings now exist will be the most 

 likely places to find gold in paying quantities ; and that it will be 

 found by searching, and that the gold-mining industry can and 

 will be carried on profitably, the author has no doubt. The quartz- 

 veins lying in the schists, which are naturally of irregular form, 

 bent and twisted, will require, however, the services of skilled 

 engineers and miners to follow them. 



About 10 miles to the east of Gubbi (40 miles east of Tiptur, see 

 Map, fig. 1), in the centre of a large gneissose area, a rock was selected 

 for microscopic examination (see Eock-section no. 10). The rock was 

 fine-grained, with a pink tinge, and consisted of quartz, felspar, and 

 mica, and in situ showed distinct foliation and may be called a gneiss. 

 Prof. Bonney remarks that its structure " recalls that of the Archaean 

 gneisses rather than of the normal granites." The author has been 

 much struck with the paucity of granite compared with the immense 

 tracts of gneiss which are found in Southern India ; and many rocks 

 called locally granite, upon examination have been found to be un- 

 doubtedly gneiss. 



A general examination of the strata on the Mysore plateau shows 

 that immense pressure has broken up the gneissose rocks, and also 

 compressed the mica- and hornblende-schists ; and it is not unlikely 

 that the above disturbance and breaking-up of the gneissose beds was 

 caused by the gradual rise of the eastern and western ghats, which 

 would create great pressure on the strata forming the Mysore 

 plateau which lies between them. 



The Mysore plateau shows evidences of having been subjected 

 to extensive denudation, from the absence of the later formations 

 and the exposures of gneissose and schistose rocks, and from many 

 masses of gneissose rocks (in some cases solitary) standing above 

 the plain at a height of from two to eight hundred feet ; also the 

 hardest of the hornblende- and mica-schists often remain in the 

 form of small hills or mountain-ranges above the level of the 

 plain. 



Having now come to the end of my notes, I shall conclude with an 

 acknowledgment of the great assistance I have derived in my work 

 from Prof. Bonney 's microscopic researches ; and I may say, further, 

 that Prof. Bonney, without having been on the ground or seen the 

 results of the chemical analyses or the large collection of rocks brought 

 home, has, with the microscope alone, read the whole story just as well 



