34 ECONOMICAL GEOLOGY. 



No. 42. Hard sandstone 3 



No. 43. Very dark shale 9 



No. 44. Limestone 4 



No. 45. Jointed flre-clay 4 



No. W. Limestone 3 



No. 47. Jointed flre-clay ". 1 6 



No. 48. Black clod-Coal No. 11 1 



No. 49. Limestone 2 



No. 50. Jointed fire- clay 3 



No. 51. Limestone 1 6 



No. 52. Bituminous shale 1 



No. 53. Dark gray shale, with plants 6 



No. 54. Sandstone, with salt-water 23 



No. 55. Dark gray shale 3 



No. 56. Conglomerate limestone 1 



No. 57. flash coal Coal No. 10 8 



No. 58. Black clod 2 



No. 59. Limestone, partly concretionary 4 



No. CO. Blackshale 1 6 



Total depth 483 11 



This shaft terminates apparently not very far above the horizon 

 of the Shoal Creek limestone, which lays about 385 feet above the 

 coal in the shafts at Sandoval and Centralia, the nearest points 

 where any of the lower coals have been opened, and it would have 

 to be sunk about 400 feet further to reach a coal seam of any prac- 

 tical value for deep mining. 



BUILDING STONE. 



Many valuable quarries of building stone have been opened in this 

 State since the publication of the preceding volumes, but from the 

 press of other duties, I was not able to give as much time to their 

 examination as was necessary to enable me to report fully upon 

 them. 



The location of the Southern Penitentiary at Chester has resulted 

 in the development of a very important industry, in connection with 

 the extensive beds of limestone and sandstone which had long been 

 known to occur at that locality, but had remained comparatively 

 useless for the want of the labor and capital necessary for their full 

 development. 



That division of the lower Carboniferous formation known as the 

 "Chester Group" comprises several beds of limestone, sandstone and 

 shale, and it is upon the lower part of this formation that the city 

 of Chester and the Southern Penitentiary are situated. The follow- 

 ing section will show the relative position and thickness of the 

 rocks exposed on the Penitentiary grounds: 



