136 STEVENSON— INTERRELATIONS OF THE FOSSIL FUELS. 



marls, with many films of bright coal and layers filled with com- 

 pressed fossils, mostly Planorbis and Melania; Lauser coal or bottom 

 bench, 2 to 2.5 meters ; gray, brown to blackish sandy marls with thin- 

 bedded calcareous marls holding coal smnts and carbonaceous shale. 



In reading this section, one might easily suppose that it refers 

 to some peat locality in northern Ohio. The coal differs somewhat 

 in the several benches but the general character is the same through- 

 out. The woody portions pass gradually into Pechkohle, which is 

 the prevailing type and is not always laminated. 



The Oligocene Coals. — In the Zsil Valley of Hungary, according 

 to Hantken,^"^ the great adit, which crosses 567 meters of Oligocene 

 rock, dipping at 30 degrees, cuts 14 beds of coal, one of which is 

 41.12 meters thick. The marly beds in contact with the coal are very 

 dark and contain carbonate of iron. At Szt. Ivan in the Gran dis- 

 trict, a bed, 12.4 meters thick, has four benches of coal, the partings 

 being freshwater limestone and in all 3.7 meters thick. It underlies 

 a conglomerate of dolomitic fragments and rests on a carbonaceous 

 shale passing downward into freshwater limestone. Partings in coal 

 beds of this Gran area show notable variations in thickness, one of 

 them increasing in a short distance from 1.9 to 17.45 meters. Fresh- 

 water conditions seem to have prevailed almost throughout, but in 

 the Nagy-Kovacsier basin, the lowest coal bed underlies shale con- 

 taining Natica and Cerithkim, though freshwater limestones are the 

 predominating rocks above. The coal shows marked variation in 

 composition. Nendtvich^^" said in 1848 that the coal of the Gran 

 region is black, with dull luster, mostly shaly but sometimes with 

 conchoidal fracture. It is non-caking and yields only a slightly 

 luminous gas. The woody character must be marked, for Nendtvich 

 speaks of the material as tough and hard to pulverize. The chief 

 drawbacks are the readiness with which it falls to pieces on exposure 

 and the tendency to spontaneous combustion. 



The Oligocene coals of Germany are found in many small areas. 

 Plettner^^^ described in detail the greater number of the compara- 



191 M. Hantken, " Die Kohlenflotze," etc., pp. 247, 259, 260-263, 280, 286, 289. 

 132 C. M. Nendtvich, " Ungarns Steinkohlen," etc., pp. 25-31. 

 193 Plettner, " Die Braunkohlen Formation in der Mark Brandenburg," 

 Zcitsch. d. d. geol. Gescll., Bd. IV., 1852, pp. 249-483. 



