KHASI HILLS. 



139 



with the sand now forming the beds of sandstone overlying the 

 limestone. These deposits of sand have naturally conformed to the 

 surfaces of the hollow into which they have been carried, but the upper 

 surface of each successive layer has gradually become more and more 

 level, the sand necessarily accumulating in greater mass in the hollows, 

 until, at a distance of about four feet from the general surface of the 

 limestone below, the beds have again become regular and horizontal. 

 This remarkable depression in the limestone, coincides with a crack or 

 joint which passes nearly vertically through all the beds below, but 

 along which there is no dislocation or faulting (Fig. 11). That the 



Rg 11. 

 limestone beds must have been considerably indurated . or at least 

 desiccated, previously to this excavation taking place, is evident from the 

 sharp and unbroken edges with which the horizontal layers of the 

 limestone conie against the sides of the sandstone filling the hollow. 

 No soft mud, such as these limestone beds originally consisted of, 

 could have remained at the steep angle of the sides of this gully. 

 And I think it also evident, from similar reasoning, that the same 



