On the ParaMdism of Coal-Seams. 341 



depths below the water level. I am led to hold the former opinion, 

 while he strenuously maintains the latter. In ray district, and in the 

 portions of his district — i. e., the one under his special supervision — 

 that I have examined, and also in the bordering States of West 

 Virginia and Kentucicy, I find a general parallelism of the seams of 

 coal, implying an even and uniform subsidence. This makes system 

 possible and stratigraphy useful in our coal-measures. If, on the other 

 hand, the subsidence were uneven and irregular, no coal-seam can have 

 its proper and exact horizon, and all things are in confusion. If, for 

 example — and I quote one of the cases given by Dr. Newberry in his 

 article — coals No. 8 and No. 9 are, at one place, 150 feet apart, and 

 have three coal-seams, 8a, 86, and 8c, intercalated between them, and 

 a few miles away they are only 50 feet apart, with no intercalated seams, 

 the mind is left in confusion and perplexity, and the practical identifica- 

 tion of coal-seams is well nigh impossible. The theory of unequal sub- 

 sidences, of "very local subsidences," of "warped and folded strata," isit- 

 self very confusing, for it requires us to believe that the old shore areas 

 held themselves in statistical equilibrium near the water's edge, during 

 the long periods in which the vegetable matter of the coal-marshes was 

 accumulating, and then settled below the water level with all sorts of 

 pitches and irregularities. That there could be such alternations of 

 perfect rest and equipoise, with irregular and lawless subsidence, in a 

 region never disturbed by igneous or other forces which have left any 

 traces of themselves, appears theoretically highly improbable. 

 According to Dr. Newberry's published sections, while his coal seam 

 No. 5 settled down 20 feet in one place, it settled in another 130 feet, 

 and further on, in the same direction, only 32 feet. Among the illus- 

 trations and proofs of this confusion-theory adduced by Dr. Newberry, 

 is the varying distance between his coal seams No. 1 and No. 2. That 

 the Briar Hill, or lowest seam in Mahoning and Trumbull counties, is 

 very irregularly bedded, I readily concede. It was laid down in 

 patches and strings in the depressions of an uneven surface of Waverly 

 or conglomerate, a surface which had probably been long subjected to 

 subaeriai erosion. When this very undulating surface, with the coal- 

 swamps filling its basins and winding hollows, subsided below the 

 ocean, the introduction of the proper coal-measure stratification began, 

 and then occur horizontally arranged sediments. Hence, the next 

 seam of coal above is, according to Mr. Reed, in a "perfectly horizontal 

 position" over areas where No. 1 shows great irregularities. Now, 

 Avhat I should expect in northeastern Ohio, would be this : That all 

 the subsequently formed seams of coal would be formed under the con- 

 ditions of No. 2, and not after the manner of No. 1, whose conditions 



