MINING 



313 



various individuals or joint-stock companies, either by themselves, or associated with 

 the Government. 



The metalliferous valley contains 5,000 inhabitants, all deriving subsistence from 

 the mines; 300 of whom are occupied in the government works. 



Each concession has a number and a name : as Antoni, Christoph, Matthseus, Os- 

 waldi, 2, 8, 36, &c. 



Fig. 1471 is a section of the quicksilver mine of Idria. 1, is the grey limestone ; 

 2, is a blackish slate ; 6, is a greyish slate. Immediately above these transition rocks 

 lies the bed containing the ores, called Coralleiierz, which consist of an intimate mix- 

 ture of sulphuret of mercury and argillaceous limestone ; in which four men can cut 

 out in a month 2 toises cube of rock. 



Fig. 1472 represents a section of part of one of the copper mines of Mansfeld ; con- 

 taining the cellular limestone, called Raitchwacke, always with the magnesian 

 limestone, called Zechstcin ; the cupreous schist, or Kupferschiefer ; the wall of greyish- 

 white sandstone, called the weisse Liegende ; and the wall of red sandstone, or the 

 rothe Liegende. The thin dotted stratum at top is vegetable mould ; the large dotted 

 portion to the right of the figure is oolite ; the vein at its side is sand ; next is Rauch- 

 wackc ; and lastly, the main body of fetid limestone, or Stinkstein. 



1472 



1471 



1473 



Fig. 1473 represents a section of one of the Mansfeld copper-schist mines in the 

 district called Burgoerner, or Preusshoheit : 1. Vegetable mould, with siliceous 

 gravel. 2. Ferruginous clay or loam. 3. Sand, with fragments of quartz. 4. Eed 

 clay, a bed of variable thickness as well as the lower strata, according as the cupreous 

 schist is nearer or farther from the surface. 5. Oolite (Rogenstein). 6. Newer 

 variegated sandstone (hunter Sandstein). 7. Newer gypsum ; below which, there is 

 8. A bluish marly clay. 9. Stinkstone, or lucullite. 10. Friable greyish marl. 



11. Older gypsum: a rock totally wanting in the other districts of the mines of 

 Eothenberg ; but abounding in Saxon Mansfeld, where it includes vast caverns 

 known among the miners by the name of Schlottcn, as indicated in the figure (1473). 



12. The calcareous rock, called Zechstein. The lower part of this stratum shows 

 symptoms of the cupriferous schist that lies underneath. It presents three thin 

 bands, differently modified, which the miner distinguishes as he descends by the 

 names of the sterile or rotten (faille) rock ; the roof (Dachklotz) ; and the main rock 

 (oberberg). 



13. Is a bed of cupriferous schist (Kupferschiefer), also called the bitumino-marly 

 schist, in which may be noted, in going down, but not marked in the figure 



a, the Lochberg, a seam 4 inches thick. 



b, the Kammschale, % of an inch thick. 



c, the Kopfschale, 1 inch thick. 



These seams are not worth smelting ; the following, however, are : 



d, the Schiefer-kopf, the main copper-schist, 2 inches thick. 



e, a layer called Locheri, 1 inch thick. 



14. The wall of sandstone, resting upon a porphyry. 



Fig. 1474 is a section of the mines of Kiegelsdorf in Hessia, presenting 



1. Vegetable mould. 



2. Limestone distinctly stratified, frequently of a yellowish colour, called lagcrhajter 

 Kalkstein. 



3. Clay, sometimes red, sometime blue, sometimes a mixture of red, blue, and yellow. 



4. The cellular limestone (Rauhkalk). This rock differs both in nature and position 

 from the rock of the same name at Mansfeld. 



