STEVENSON— INTERRELATIONS OF THE FOSSIL FUELS. 137 



lively small basins within Brandenburg, where the coals are of great 

 importance. At Wittenberg, on the Elbe, where the bed is 8 to 12 

 feet thick, the coal is blackish-brown and pulverulent; the inhabi- 

 tants wet it and mould it into bricks. The upper part of the bed con- 

 tains much fine quartz sand, but there is none in the lower portion. 

 The dips vary from 9 to 20 degrees. A rather extensive basin is near 

 ]\Iuskau, on the Neisse River about 70 miles south of east from 

 \\'ittenberg, where the coal is hard, imperfectly laminated and shows 

 numerous imprints of leaves on surfaces of the laminse. It rests on 

 a fine clay and underlies about 10 feet of sand, succeeded by 5 inches 

 of leaf-bearing clay, above which is another coal bed of unknown 

 thickness. The coal is dull with earthy fracture and shows no trace 

 of organic structure, aside from the leaf imprints. A yellow resin, 

 mealy or dust-like, is abundant. At Griineberg, 50 miles northeast 

 from Muskau, the coal is hard and laminated ; it is dark brown but 

 the included plant remains, heaped in great quantity on the surfaces 

 of laminae, are yellowish brown. The waxy yellow resin is plentiful 

 and is often enclosed in the fossil wood, especially between the 

 annual rings. 



Fiirstenwalde is near the river Spree at a few miles west from 

 Frankfurt a. O. Plettner has preserved the records of numerous 

 shafts and borings, which exhibit such variations that the coal beds 

 must be lenses. The dips are from 20 to 70 degrees. The important 

 bed is triple. The great bench at the bottom, 10 to 11 feet thick, is 

 the best and usually contains little Formkohle ; but, at times, that type 

 of coal forms most of the upper benches. There is a notable differ- 

 ence in quality, coal from the middle bench being the worst. Plettner 

 in this district distinguished three types of coal, which he recognized 

 elsewhere : ( i ) Knorpelkohle, the hardest and most appreciated, 

 brownish to coal-black, with at times a bluish luster ; it breaks into 

 Knorpel or sharp-angled parallelopipedons, 2 to 9 inches in diameter ; 

 the fracture is earthy, luster none and plant remains are not common ; 

 (2) Erdig- or Formkohle, light brown, of loose texture, earthy, fri- 

 able. (3) Bitumenose Holz, which is present in all benches of a bed, 

 embedded in the coal ; sometimes it is fragmentary but at others 

 whole stems are found ; these are usually prostrate, erect stems being 



