194 Captain J. Franklin on the Geology of a Porlion of Bunddcund, 



is always compact, usually dendritic, and presents frequently on its surface 

 irregularities which represent the interlacings of ivy. 



This limestone extends over the platform of the second range of hills, and 

 covers it with a tiiin stratum, the continuity of which is interrupted only by 

 the occasional protrusion of the red marl or sandstone on which it rejjoses. 



After passing- the town of Pureriah, I came upon the overlying rocks which 

 I designate by the general term of trap. The hills on the left of the road are 

 composed of these rocks, and after ascending the pass of Pureriah I met 

 with no other descrijjtion of rock between it and Saugor. 



The upper part of the trap of Pureriah, like that of Saugor, is generally 

 composed of boulders imbedded in friable wacke, and vary in size from that 

 of an eg*f^ to that of a large bomb-shell. They are formed of concentric layers, 

 which are sometimes very thin and often numerous. 



Under the stratum of boulders, which occupies the highest parts, is a bed 

 of indurated wacke lliat passes into basalt, and is occasionally vesicular. 

 Beneath it is a stratum of earthy limestone. 



I have termed this rock earthy limestone, because I know not what other 

 name to give it. Its principal component is carbonate of lime; and next to 

 that is alumine; it also contains silex, and, when this earth abounds, the rock 

 is converted into chert; on the other hand, when ferruginous clay abounds, 

 it passes into jasper. It occasionally assumes the texture of highly indurated 

 clay, and sometimes, though very rarely, the hardness of clinkstone, but, 

 generally speaking, it is friable. On the borders of the trap where it is always 

 found, if the trap reposes on sandstone, it contains nodules of sandstone im- 

 bedded in it. 



Below the limestone is a stratum of amygdaloid, containing calcareous spar 

 and occasionally zeolites. Sometimes it resembles the toadstone of England ; 

 and it has been ascertained, by the excavation of wells, that it reposes on sand- 

 stone at Saugor. I have not met with it in situ in any other part, except 

 some indistinct vestiges near lysinghanugur. 



From Saugor I proceeded southward by lysinghanugur to Tendukaira, 

 and met with no rock except trap, which contained abundance of chalcedony, 

 semi-opal, mealy zeolite, cacholong, agates, jaspers, and heliotrope, until I 

 descended the range of hills which forms the northern barrier of the valley of 

 the Nermada river. 



This great valley is favourable for throwing light on the primitive rocks of 

 the central chain, as the overlying beds appear to have been removed, and 

 the older strata exposed to view. The whole mass of overlying rocks which 

 had been previously passed, reposes on red marl or sandstone ; as is apparent 



