60 MALLETj VINDMVAN SPJRIES. 



of Kuclhur the black shale (Bijigurh) rests directly on the Rotas 

 limestone^ while the lower sandstone intervenes in other localities, attain- 

 ing at Bijigurh a thickness of 200 feet or more. The lowest beds of 

 the Kymore group, therefore, must have been deposited rather irregularly, 

 or in patches. This is also indicated by the existence of lower Vin- 

 » dhyan debris 100 feet or more from the base of the upper series, as 

 when this thickness of strata had been formed in one place, the lower 

 rocks must have been still exposed in that whence the debris was derived. 

 The lower Kymore sandstone appears to attain its maximum thickness 

 near Bijigurh, thinning out from this both east and west. At Burdhee 

 where the shales become extinct, and beyond which the lower sandstone 

 can no longer be distinguished from the upper, it is much thinner than 

 at Bijigurh. ■ ^ 



The thickness of the shales at the latter place is 150 feet or so, and 

 about the same in the Doorgowtee valley. A section in one of the 

 lateral gorges exhibits ' penciF shales, quite black and intensely brittle, 

 covered 2 or 3 inches deep with minute sharp-pointed fragments. They 

 are intersected by joints which have a rusty appearance from decom- 

 posed pyrites, and some are marked by veins 1 or 2 inches thick of the 

 impure mineral; the shale itself often weathers red from the same 

 cause. A little higher up the stream the latter are mixed \^^th a large 

 proportion of black and dark-colored sandstone ; the shale on the 

 weathered surface is perfectly black, and looks exactly like impure coal. 

 In general it consists of bands of pure shale and thin-bedded shaly 

 sandstone. The passage into the upper sandstone is sudden, the beds 

 being generally interstratified for 2 or 3 feet at the jmiction. It 

 was these shales which were mistaken for coal at Bijigurh,"^ and origi- 

 nated the rumour of the existence of that mineral in the Kymore hills. 

 Owing to their pyritous nature, efflorescences of sulphate of ii-on and 

 alum are common, and have been economised to a small extent. 



* Ante p. 8. 

 ( 50 ) 



