GEOLOGY. 153 



they occur, and that through greater differentialization ; 

 they have even receded for the most part into acid and 

 alkaline poles, as calc-spar, fluor-spar, heavy-spar, which 

 are the usual vein-stones. All vein-stones are oxyds and 

 as a rule, those in which the oxygen is freely manifested, 

 namely as acid. The vein-stones were the sheath of the 

 ore, which could first appear when this sheath had with- 

 drawn itself. 



724. The metal stands in relation to the vein-stone. 

 Thus in argillaceous vein-stones we commonly meet with 

 iron, manganese ; in the quartzoze with gold ; in the 

 calcareous with lead, &c. There are here also extremes. 

 There are vein-stones, called sterile veins, in whose 

 antagonism no metal has been formed ; and there are 

 veins, that are merely filled with metal, such as the Stock- 

 werke, Lager. 



725. Since the ore and the vein-stones thus originate 

 together, and in such a manner that they conditionate 

 each other ; their fundamental mass must have been one, 

 and a separating force, which is not light, must have ope- 

 rated upon them. 



726. Moreover, as the ores occur only in narrow 

 spaces with their vein-stones and both form alter- 

 nating tables upon the walls of the veins, they must have 

 been attracted by the latter. 



7:27. The walls of the vein consequently exert a polar 

 influence upon the ore and vein-stone. Now, if this 

 be their mode of action, they must be in a condition to 

 separate the fundamental mass. 



728. It is thus the vein themselves, which, by a vital 

 force, produce the metals ; they are thus a living womb, 

 or matrix as it has been emphatically termed. 



729. Two walls in close juxtaposition are requisite for 

 the production of metal. Upon a freely exposed wall or 

 face of rock no metals are found. 



730. By this separation, however, two kinds of mine- 

 rals originate, Inflammables, and ores proper or metals. 

 The action of the walls must be therefore of a twofold 

 nature. 



