Metalliferous Veins. 3/ 



is in favour of the above assertion, that the idea of vein-for- 

 mations does not admit of being referred to definite principles, 

 and these formations themselves cannot be characterized by 

 fixed characters, yet, as so great a diversity of differences does 

 not occur in all places, this idea ought always to be kept in 

 view in the investigation of a district for the presence of re- 

 positories of this kind, the known veins ought always to be 

 studied thoroughly in this point of view, and we ought not to 

 doubt but that, in this way, much may be acquired and 

 learned, and that much instruction may be obtained for ap- 

 proaching our desired object, of which we should have been 

 deprived without this information. 



Besides the greater collections of veins which, in what has 

 now been said, have been termed vein-magazines or depots, 

 and vein-districts, there are others of smaller extent which are 

 well deserving of enumeration. The first is that in which the 

 large principal vein is accompanied by narrower, often also 

 less extensive repositories of the same formation which afe 

 termed companions (Gefahrten), just as in the vicinity of a 

 large mass of granite, we not unfrequently find smaller por- 

 tions of the same rock, in every variety of forms. The second 

 consists in this, that sometimes several small veins, of similar 

 constitution, occur so near one another, that they are only se- 

 parated by slender stripes of the containing rock, and thus 

 admit of being mined together ; and that of such collec- 

 tions, several are found together in a parallel position, and 

 at small distances apart. The intermediate rocky matrix often 

 includes the ores which occur in the veins, either disseminated 

 or in small massive portions, and this also sometimes happens 

 when the veins contain but little, or are altogether barren. 

 The third of these collections, finally, contains a greaf num- 

 ber of small, chiefly irregular veins of one formation, whose 

 thickness still amounts to something, which s» run through 

 one another in all directions, that they cross in the most di- 

 versified manner, seldom penetrating, but sometimes causing 

 shifts. The spaces which such veins occupy in rock-masses are 

 completely without determinable limits, and the whole pheno- 

 menon is therefore specially remarkable, beoause it places in the 

 most intimate connection the real and characteristic veins with 

 those in the previously described so-termed stockwerks, and which 



