78 Revieivs — Indian Geology. 



Bellary District lies between Haidarabad on the north, Mysore 

 on the west and south, and Anantapur on the east. It forms the 

 western division of the Ceded Districts (so-called because ceded by 

 the Nizam by treaty in 1800 to the East India Company) ; it lies in 

 the centre of the Deccan tableland, and has an area of 5,904 square 

 miles. Nearly the whole area has a general slope to the northward, 

 and is drained by the Tungabhadra Eiver. Thirty-one hills are cited 

 by the author having altitudes varying from 1,674 feet to 3,285 feet. 



The rocks of the district are arranged in four principal groups — 



IV. Recent and t Suhaerial. — Talus formation. Cemented Taluses. 

 Post-Tertiaky. 1 Pseiido - Lateritic Breccias. Kankar formations. 

 j Blown sands. Eegur. Red soils. Mixed and white 

 \ soils. 

 Alluvial. — Modern Alluvial deposits (loams and shinp^le 

 beds) of the Tungabhadra and its tributaries. Fossili- 

 ferous Travertine. Consolidated shingles. High- 

 level gravels (old alluvium) of the Tungabhadra. 

 Shingle fans. 

 III. Tertiary (?). Terrace Laterite. 

 II. Lower ( Dharwar System. — Principal metalliferous rocks of South 



Transition. \ India. 



I. ARCHiEAN OR \ 



Metamorphic I Granitoids and gneisses with associated traps, etc. 

 AND Plutonic. ) 



The Archaean rocks, which form the fundamental series in the 

 peninsula, are very largely developed in the Bellary District, and 

 occupy fully five-sixths of its area. Their extent alone, therefore, 

 renders them the most important geological series to be treated of; 

 they are deserving of much interest, and of far closer study than 

 could be bestowed upon them, because of their general poverty 

 in minerals of economic importance, to the quest for which much 

 more time had to be devoted. 



Taking the district as a whole, it must be described as consisting 

 mainly of granitoid rocks, generally of porphyritic character, the 

 metamorphic or gneissic crystallines playing a very subordinate 

 part in most places, though of such great importance in other parts 

 of the Madras Presidency. 



The description of the Archsean or metamorphic rocks occupies 

 the whole of chapter iv, pp. 26-73. 



" Very marked and interesting illustrations of the power of 

 weather-action along lines of jointing are to be seen on the top of 

 the Fort Hill in the shape of water-holes which have been utilized 

 as cisterns. In every case the weathering has worked along lines 

 of jointing and produced the remarkable holes which are so useful 

 in holding rain-water, and of which the native builders availed 

 themselves so fully by increasing the water-holding capacity by dams. 



" Some people seem to think the constant supply of water in these 

 holes a rather mysterious phenomenon, whereas it is in reality a very 

 simple one. The several catchment-areas which supply the holes 

 are more than large enough to fill them in good rainy seasons, and 

 the larger holes are so deep that their stock of water cannot evaporate 

 more than partially before they get a fresh supply from the skies, and 



