566 



SUPPLEMENT. 



the thickness of the vein; while the sides mark 

 the declination from the vertical through the 90 

 degrees to the horizon. But a little sketch and 

 explanation, given in the appendix, will explain 

 this subject better than any verbal description. 



The rock which covers the vein, is called the 

 roof; and the bottom is called the sole. They 

 are also called the hanger and the ledger. The 

 English miners also use the word hade, to denote 

 the inclination : and rake vein, to denote the per- 

 pendicular, while the pipe vein approaches the ho- 

 rizontal. The veinstones are sometimes called 

 riders : and the German word loch is retained for 

 a cavity or empty space. 



Saibands. The vein rarely coalesces with the rock, but is 

 separated from it on both sides by what are called 

 the salbands, which, like walls, contain the mine- 

 ral : and often by the skirts, in German besteg, 

 which are small layers of earthy matter, commonly 

 argillaceous, lying between the salbands and the 

 rock. In the veins themselves the ores are ac- 

 companied with their gangarts of quartz, barytes, 



Cavities, calcareous spar, &c.* There are also cavities, 

 which in powerful veins are of proportional ex 

 tent, so as to appear like chambers, studded all 

 over with druses, or groups of beautiful ores and 



* See Brongniart, ii. 282. 



