SYNOPSIS OF PREVIOUS OBSERVATIONS. 31 



He recos^nised the fact that the upper quartzites (formiug his 

 fourth sandstoue range) to the south of the Bagalkot valley overlies the 

 limestones and shales conformably, while both Dr. Christie and Captain 

 Newbold had thought that an unconformity existed between them. 



His theory of the volcanic origin of the breccias was arrived at 

 by studying one of the sections in this quartzite ridge, and seeing to 

 what an extent some thin beds were comminuted by excessive jointing. 

 He conceived it possible that convulsive movements then supervening 

 might mix up these fragments with the associated clays, and thus 

 produce a clayey silicious breccia. 



It is very hard to understand what difficulty Mr. Aytoun found 

 in recognising the stratification of the sandstones of the Baclami and 

 Jalihal hills, for it is remarkably clear and distinct as a rule, though 

 the beds are of great thickness and often of very coarse texture. 



The subaerial talus of sand derived from the degradation of these 

 coarse sandstones was thought by him to be due to the action of some 

 river not now in existence. ' . 



His description of the Kaladgi valley is fairly accurate, but his section 

 No. 9 is a mere diagram, and quite wrong as to the position of the 

 Deccan Trap as shewn above, when referring to section 1. In conclusion, 

 he mentions the occurrence of green copper stains on surfaces of the 

 limestones near Kajadoni, south-west of Kaladgi, and speaks of possible 

 causes for the paucity of the supply of that metal. 



Two minerals, which, according to the list appended'to his paper, are 

 very common in the lateritic region above referred to, namely, pyrolusite 

 and psilomelane, were only observed by me in very small quantities as 

 films or thin coatings or minute veins in laterite and haematite fragments. 



Another paper by Mr. Aytoun, referring partly to the country under 

 report, had been communicated the year before {i. e., 1853) to the 

 Bombay Geographical Society, the title of which was ^' Geological 

 structure of the basin ^^ of the Malprabha in the Collectorate of Belgaura, 



( 31 ) 



