42 STEVENSON— INTERRELATIONS OF FOSSIL FUELS. 



15.8 to 19.9 of ash; but near Rehgarten, the same beds yield a, coal, 

 with only 7.8 per cent, of ash ; at Loichgraben, the lower seam has 

 good coal, while that from the upper seam, though in appearance 

 equally good, has 52 per cent. Coal is mined near Gossburg, which 

 contains upwards of 30 per cent, of ash. Rachoy has shown clearly 

 that in both Jura and Trias a seam varies greatly in this respect in 

 different portions of its area. 



There are numerous coal seams in the Steierdorf-Anina area of 

 Hungary, but only 5 of them are workable — each of these in limited 

 spaces. They are divided into benches, some containing good coal, 

 the others worthless. Samples of good coal from the highest two 

 have from 1.28 to 7.26 of ash, while those from the third have from 

 2.56 to 16.78. The fourth seam shows less variation, the percentage 

 being 3.44 to 5.65. Within the Fiinfkirchen region, 174 seams were 

 crossed by the tunnel at Vasas, with a total thickness of 52 meters. 

 Thirty-nine of them, 14 meters thick, are "dirty" and worthless; 

 of the 28 seams, which are workable in areas, large or small, at 

 least one third become at times too impure to be mined. Hantken 

 gives 26 analyses; 5 show between 16 and 20; 7, from 12 to 15; 

 4, from 10 to 12 and only 5 have less than 6 per cent, of ash. All 

 of these are from mines in full operation. 



The brown coal of the Tchoulym field in Siberia has at most 

 only 2.28 of ash in the samples analyzed but, apparently, the same 

 horizons in the North Tchoulym area yield coal with more than 30 

 per cent. 



The Ipswich seams of Queensland have from 19 to 31 per cent, 

 of ash, while the Burrum coals are all remarkably free from 

 mineral matter, the highest percentage being only 8. 



The analyses of specimens from the two benches of a coal seam 

 in the Dan River district of North Carolina show 9.65 in the upper 

 bench and 20.27 in the lower. The best coal in the area has only 

 5 to 6 per cent., but other samples of " best coal " contain from 

 20 to 39 per cent. Samples taken by the early students in the 

 Richmond basin were all from the mines then in operation. The 

 lower division of the great seam is usually described as much in- 

 ferior to the higher portions. In most cases, the samples appear to 

 have been chosen from the better portions, for the ash rarely exceeds 



