Asphaltic Coal. 105 



XT. — On an Asphaltic Coal from the shale of the Huron 

 River, Ohio, containing seams of Sulphate of Baryta. 



By PROF. ALBERT R. LEEDS. 



[With a Geological Note by Dr. J. S. Newberry.] 



Read January 11, 1S75. 



I have received from Chas. N. Smith, Esq., of Nbrwalk, 

 Ohio, a specimen of coal found on the Huron River, below 

 the Lake Shore and Michigan Southern R. R. crossing. It oc- 

 curs in a bank of shale, about seven feet below the surface of 

 the ground, and a few feet above the bed of the river. The 

 specimens forwarded to me for examination were three and a 

 half centimetres in thickness. According to my informant, 

 the thickness of the seam at its outcrop, and for a distance 

 back of three feet, averages about two inches. It then 

 divides into two seams, which are separated by a thin stra- 

 tum of shale. The remarkable and, as we believe, novel 

 fact concerning these seams of coal, is that they are traversed 

 by innumerable sheets of sulphate of baryta, which divide 

 the coal into small irregular fragments. The coal itself has 

 a brilliant lustre, resembling asphalt. The white mineral 

 traversing it, consisted, in the specimen examined, of 88.61 

 per cent, of sulphate of baryta, the remainder consisting of 

 silica, alumina, and oxide of iron. By weathering, the sur- 

 face of the sheets of white spar becomes stained yellow with 

 ferric oxide. The causes which have operated to produce 

 this deposition of barytes in the coal, whether by infiltration 

 of meteoric waters percolating through overlying strata, or 

 by some other agency, must be determined by an examina- 

 tion of the local stratigraphy. 



Note by Dr. J. S. Newberry. 



The mineral in question occurs in numerous localities in 



Ohio and Kentucky, filling narrow fissures in the Huron 



shale. This formation, which is the equivalent of the Por- 



May, 1875. 8 Ann. Lyc. Nat. Hist., Vol. xi. 



