VARIA TION AND EQUIVALENCE OF SANDSTONE 463 



the series toward the south, until it probably includes the Kit- 

 tanning horizon, as shown by the fossil flora found in the coal bed 

 (A) at Clendenin twenty miles northeast of Charleston. In sup- 

 port of this proposition the writer called attention to the disap- 

 pearance of the uppermost bed of sandstone of this group at 

 Sutton, W. Va., and the lowering of the upper limit south of the 

 river by 200 feet, but this being an isolated example, was not 

 given much weight in the discussion of the subject. Recently, 

 however, an excellent example of the variation of these rocks 

 has been brought to the writer's notice and incontestible evi- 

 dence furnished regarding a marked change in its upper limit 

 between Charleston and Clay. The five sections given in Fig. 2 

 show something of the nature of this variation, but many inter- 

 mediate sections might be interpolated so as to make the transi- 

 tion complete. 



Throughout the region the base of the formation generally is 

 marked by the presence of a bed of black flint which occurs only 

 a short distance above the Stockton or Lewiston coal bed that 

 has been regarded as the equivalent of the Upper Freeport coal. 

 This is the only bed of flinty character known in the region, and 

 it is easily identified by its debris, which decays so slowly that it 

 is almost always in evidence along the outcrop of the bed. The 

 flint is a local feature covering an ellipsoida' shaped territory, 

 whose longer axis lies east and west, and extends from Charles- 

 ton to near Summersville, in Nicholas county. In a north-south 

 direction it is more limited, reaching only a few miles south of 

 Kanawha River in the vicinity of Brownstown and Montgomery, 

 and showing on Elk River in the vicinity of Queen Shoal. Toward 

 the north and west the horizon of the flint passes below water 

 level, but in many places it loses its flinty character before dis- 

 appearing and becomes a silicious shale which cannot be dis- 

 tinguished from adjacent beds. Throughout the region here 

 discussed, which lies between Charleston and Clay the flint is 

 generally present, and it affords an ideal datum from which to 

 measure. 



At Charleston the sandstone overlying the flint has a total 

 thickness of about 320 feet, and its general characteristics are 



