230 On the Alpine Glacier, Iceberg, [No. 159. 



Voysey, nor a modern alluvium washed from the trap rocks as thought 

 by Christie, but a deposit from water in a state of repose, or nearly so. 



The principal objections to these theories of Voysey and Christie are, 



1st. The great extent and geognostic position of the regur, cover- 

 ing both the tabular summits of hills, the bottoms of vallies, vast 

 almost treeless plains, with a sea-like horizon tality of surface, often far 

 removed from the least influence of existing rivers and low floods. Its 

 occurring in broad detached patches often far above the long, narrow 

 lines of drainage. 



2nd. Its underlying occasionally all present alluvial soils, those of 

 the trap included, and filling up chinks and fissures in the subja- 

 cent rocks. 



3rd. Its overlying granitic, hypogene, sandstone, limestone, and 

 lateritic rocks indiscriminately, far distant from trap rocks which it 

 also overlies. 



4th. All trap rocks in weathering, redden by peroxidation of the 

 protoxide of iron they contain ; and usually form first a brown, then 

 a reddish-brown, or coffee-coloured soil. 



5th. The regur, at a distance from trap rocks, imbeds no frag- 

 ments of them, even of their hardest and most lasting vein stuff, such 

 as quartz, jasper, heliotrope, agate, and calcedony. It often imbeds 

 fragments of whatever rocks it may happen to overlie, or which are 

 washed into it. 



6th. The remarkable homogeneous character and colour of the regur 

 over large areas, when free from recent foreign admixture, to which it 

 is subject, as well as to re-arrangement from present rains and inun- 

 dations. 



7th. The different colour, generally shades of brown and red, of the 

 present fluviatile deposits of Southern India, and their varying charac- 

 ter over small spaces even. 



In common with some clays of the boulder deposit, the stratification 

 of the regur is rarely apparent, and always obscure. But this 

 phenomenon I have observed in the mud of tanks over which the 

 water has been deepest and stillest, and where the particles deposited 

 were of a very fine and homogeneous character. In proportion as the 

 nature of the mud deviated from these conditions, and became inter- 

 mixed with silt and sand, the layers of deposition became more and 

 more distinguishable. 



