Lesley.] 50 [April. 



purest limestone. Its lowest strata contain, in many places, 

 large dark green flint pebbles, which seem to have been ex- 

 tensively quarried by the aborigines. Traces of lead are 

 found through its centre beds. The drainage through it is pe- 

 culiar. The valleys excavated in it are dish-formed, broad, 

 and shallow, and rarely have streams flowing through them ; 

 for the waters of the springs above are carried down through 

 sinkholes and cracks in the cavernous limestone, and often 

 reappear only to plunge again and again, before they finally 

 gush out in copious, clear, and never-failing springs, along 

 the junction of its base with the next underlying Knobstone 

 formation, near the mouths of the valleys, as they open to- 

 wards the Blue Grass country. We have thus valleys which 

 are technically dry, the bottom being a mere series of dry, 

 crater-shaped holes, where cattle graze.* In Bath County 

 (70 miles west-northwest of Paintsville), the valleys are ter- 

 raced with two lines of springs, an upper line of warm soft 

 water coming from the coal shales under XII (85 feet thick), 

 and a lower line of cold hard Avater, issuing from the base of the 

 XI limestone,t 140 feet thick. In Powell County (60 miles 

 west of Paintsville), the limestone is thick and cavernous; 

 sinks and caves are seen on every hand ; the cavern roofs fall 

 in and let down the upper ore and coal measures, so as often 

 to baulk the miners of their bed, over large areas. | On Rock 

 Lick and War Fork, in the north corner of Jackson County 

 (about 45 miles W. S. W. of Paintsville), the great thickness 



* Copied in substance from J. Lesley, Ken. Eep., IV, 452. 



f Idem, p. 466, 467. See, also, the description under the head of 

 Kockcastle County, page 482. 



J Ken. Rep., IV, p. 472. Between Roundstone Creek and Kentucky 

 Eiver Valleys, in Rockcastle County, where the Conglomerate XII is 

 very thin, and only in fragments on the upland, a remarkable number 

 of holes occur in it, only to be accounted for by reference to the caver- 

 nous nature of the underlying limestone, on which it almost immedi- 

 ately rests, the shales of XI having run down from 240 to 40 feet. The 

 No. XI limestone measuring variously 115, 145, 182, 220, and 240 feet, 

 the last in the southeast corner of the county. The " cavernous" mem- 

 ber of XI is described as being about 100 feet down from the top of the 

 limestone. I think it possible that the downthrow (of XII) of 150 feet 

 at Davis's Fording may be due to the same cause. 



