MAHONING COUNTY. 793 



wood. The laminated structure, visible in most coals, and especially 

 conspicuous in this, seems due to alternations of greater and less quanti- 

 ties of water in the coal marshes. This would give somewhat different 

 character to the sheets of carbonaceous matter which accumulated in the 

 different intervals. This banding has perhaps been subsequently much 

 increased by great vertical pressure, which has reduced the zones, once 

 an inch or two in thickness, to mere sheets. In confirmation of this 

 view, it may be said said that all our open-burning bituminous coals — 

 the Brier Hill, the Brazil, and . the Hocking Valley furnace coals — show 

 a distinctly laminated structure, and hackly fracture ; while the more 

 bituminous varieties of Coal No. 1, the Mineral Ridge, and Massillon 

 coals show broader, smoother, and more lustrous surface of fracture, and 

 the highly caking coals exhibit this feature in a still higher degree. 



The stratum immediately overlying Coal No. 1. is gray or black shale, 

 usually the latter. Above the shale is sandstone ; sometimes in a single 

 bed of great thickness; sometimes divided, which I have called the Mas- 

 sillon sandstone. It is seen in many places on the sides of the Mahoning 

 Valley, where it furnishes most of the building stone used. Its greatest 

 known development is at the Foster shaft, where it has a thickness 

 of one hundred and forty-six feet. At Wick and Wells' shaft, on the 

 east line of Austintown, it is also very thick, one hundred and twenty 

 feet ; but its local and irregular nature is- well shown by its variableness 

 in the vicinity of these mines ; for example, at the Kyle shaft, about a 

 mile east of the Foster, it is said to be only eleven feet thick, and at 

 Andrews & Go's shaft, less than a mile south-east from this point, it has 

 again thickened up to eighty feet. In the Mineral Ridge belt the sand- 

 stone is generally from fifteen to fifty feet thick, and in the most south- 

 erly mine of this belt, the Harroff Slope, it is said to be wanting. In 

 the western counties of Pennsylvania this rock becomes a Conglomerate 

 that has been often mistaken for the true Conglomerate, which lies be- 

 low the coal. The color of the Massillon sandstone is generally yellow- 

 ish brown, but it is often either generally tinged or mottled with pink. 

 It is rather coarse-grained, but frequently supplies a very handsome and 

 durable building stone, as is shown in the new court-house at Youngs- 

 town. 



Coal No. 2. 



Where the Massillon sandstone has not cut out other strata, the inter- 

 val of two hundred feet above Coal No. 1 consists of a number of alter- 

 nations of gray and black shale and sandstone, in which a thin coal 

 seam is frequently found from fifty to eighty feet above Coil No. 1. This 



