228 FOOTS : south mahratta country. 



" There are numerous instances where this rock occurs further east, 

 " forming patches which in many cases may be outhers of the great mass, 

 " though oftener occurring at a lower level, being the products of the 

 " denudation of the older laterite. These often have the appearance of 

 "true laterite, but are more generally found as gravel, sandstone, 

 "conglomerate, &G.'''' 



2. — Lacustrinb Formations, 



Few observers traverse the long valley, extending from a little west 

 of Amingarh (Ameengurh) past Bagalkot up to Kaladgi without being 

 struck by the idea that before the rivers which now drain the Kaladgi 

 limestone basin had cut their beds to their present depth, a lake 

 must have existed here. An examination of the lie of the lateritie^ 

 formation which occupies a great part of the surface of this old 

 valley seems to support the lake theory, which will at once account for 

 the peculiar position of the old ferruginous mud banks at which the 

 laterite was deposited. 



The sources whence the ferruginous mud, or a great part of 

 „ . J it, was obtained lie close at hand in the vast 



Ferruginous mud ' 



whence derived. -[^q^^ ^f hffimatite and hsematitic silicious schist 



of the gneiss area. A minor supply would in parts be derived from 



some of the conglomerate beds of the Kaladgi series which are mainly 



composed of debris of the great haematite beds. Yet another source of 



iron not much inferior in richness to those in the gneiss is to be found 



in the hsematitic jaspery schists belonging to the Kaladgi series, and 



occurring in the hill ridge west of Bilgi. 



Another source of the iron in the laterite exists in the Deccan trap, 

 which in many parts contains numerous grains of magnetite. 



* The name laterite is used for this ferrugino-argillaceous deposit, as it is considered to 

 be of originally sedimentary origin, though very much altered subsequently by atmospheric 

 influences. 



( 228 ) 



