White.] ^^^ [June 17, 



58. Massive, very bard, grayisli-white fine grained sand- 



stone, with some small pebbles, exhibiting in its 

 lower portion between the layers, at intervals of 2' 

 to 3' a kind of imperfect crj^stallization, by which a 

 vertical section through the layers much resembles 

 along the bedding planes the large interlocking teeth 

 of an animal. This peculiar structure Avas observed 

 at localities 2 ms. distant, and seems to be character- 

 istic of this stratum in the Piedmont region. Seen 

 forming a long line of cliffs on the Marj^land side of 

 the Potomac, 1 mile below Piedmont, and also cap- 

 ping the summit of the Front Ridge Allegheny on 

 the W. Va. side, 2 ms. below Piedmont 45' 0" 



59. Goal shale 5' 0" 



60. Concealed with some shale and flaggy S. S. visible. . . 145' 0" 



61. Sandstone, massive 10' 0" 



62. Bituminous shale 10' 0" 



63. Sandstone, flaggy 10' 0" 



64. Sandstone, massive, whitish (base of XII) 20' 0" 



65. Goal, seen at roadside along the Maiyland shore of 



North Potomac, 1 m. below Piedmont 1' 0" 



66. Sandstone, drab 4' 0" 



67. Fireclay and shale 3' 0" 



68. Sandy shale , 4' 0" 



69. Shales, brown, containing iro?i ore 10' 0" 



70. Bed shale 10' 0" 



71. Sandstone, flaggy, greenish-gray, with much shale. . . 40' 0" 



72. Concealed 40' 0" 



73. Sandstone, somewhat massive, greenish-gray........ 20' 0" 



74. Concealed, but shoAving occasional appearances of red 



shale, and very probably largely composed of that f ^^^' 



material 375' 0" 



75. Sandstone, somewhat massive, but often inclined to 



be flaggy, greenish-gray; seen in cliffs along the B. 

 & O. R. R. cuts, near the 205th mile post from Balti- 

 more, below Piedmont 130' 0" O 



76. Red shales 35' 0" 



77. Shales, greenish, sandy , 20' 0" 



78. Bed shale to level of B. & O. R. R. track at little run 



76 rods east from the 205th m. p. from Baltimore ... 10' 0" 



79. Concealed 150' 0" 



80. Limestone, gray, fossiliferous, containing Spirifer 



keokuk, Athyris sub-quadrata, Productus cora, Hemi- 

 pronites crassus, and many Crinoidal fragments. . . . 10' 0" 



81. Concealed, but probably containing several layers of 



limestone 90' 0" 



82. Limestone, gray, massive 5' 0" 



