Chap. 6.] w. blanford, western indta, 39 



marked cleavage is originally due. It is very clear that the breccias are 

 formed of fragments of a pre-existing quartzose rock cemented together by 

 jasper^ a form of silica usually supposed to be deposited from water, and it 

 is also certain that, in some instances, the fragments of the quartzite have, 

 scarcely been moved from their original position, so that shattering in 

 situ (whether by a sudden shock or by continued unequal pressure is 

 immaterial), and the deposition of silica from solution in water in the 

 cracks, would account for the phenomena. But if this be the explanation, 

 the shattering process must have been frequently repeated, and the infiltra- 

 tion have taken place after each production of cracks to have caused the 

 latter to have been so wide, and the position of the angular fragments in 

 many cases so utterly irregular as it is. 



The connection between the Bijawurs and the metamorphics is one 



_ Connection between Bi- ^^ ^^ ^^^^^ interest. Although by no means clearly 

 jawurs and metamorphics. made out the impression produced by the rather 

 rapid survey which was made of the country was that the two passed into 

 each other in all probability. There was only one spot where this appeared 

 to take place, viz., north-east of Jobut, and even there it is possible 

 that faults were overlooked, but the complete representation of beds in 

 one series by corresponding rocks in the other, foliated limestone by 

 laminated crystalline marble, hornstone by quartzite, slate by felspathic 

 schist, ferruginous breccia by magnetic iron and quartz in laminae, trap 

 by hornblend schist, &c., is in favor of the identity of the two. There is 

 even frequently more exact resemblance traceable than is due to the mere 

 occurrence of beds of the same composition. Thus the peculiar limestone 

 with thin laminse of quartz in the Bijawurs is represented by a precisely 

 similar rock in the metamorphics, only differing in the carbonate of lime 

 being more crystalline. In any case it is perfectly clear from the remarka- 

 ble parallelism already pointed out between the lamination of the gneiss 

 and the cleavage foliation of the Bijawurs that the latter series existed 

 and had undergone cleavage before the former were metamorphosed, for 



( 201 ) 



