Belations of Trap-Bocks with Ores of Copper. 19 



trap-rocks to which they are suboi'dinate, follow the contours 

 of the masses, and, at the same time, the stratified direc- 

 tions of the upraised deposits. All the three exhibit distinct 

 mineralogical transitions, which unite, on the one hand, 

 the rocks evidently eruptive, and, on the other, the rocks 

 evidently stratified. Finally, all the three are partially 

 charged with red peroxide of iron, too abundant to admit of 

 the supposition that it arises from the superoxidisation of the 

 pre-existing iron, and which, according to all probability, 

 ought to be ascribed to special emanations. 



On studying the relations of the schal steins with metalli- 

 ferous repositories, we shall find further occasion to point 

 out other identities. Let us take an example which will af- 

 ford us an opportunity, in the first place, of stating precisely 

 the conditions of the position (^giseinent) of the greenstones, 

 the schalsteins and stratified rocks of Dillenburg, and then to 

 describe the direction and composition of the metalliferous 

 repositories found in these formations. 



To the north of Dillenburg, the valley of the Dill is en- 

 closed by mountainous groups v\hich contain mines of 

 copper worked for a long period, but now only on a small 

 scale. On the left bank, an English company has opened 

 pretty extensive works in the neighbourliood of Nanzenbach ; 

 and, on the right bank, many German companies are scat- 

 tered about, particularly above the village of Weidmansheil, 

 where the mines of Stangenwaage, Bermausglucke, Gnade- 

 Gottes, and Haus-Nassau are situated. The formation con- 

 taining these varied repositories is in very strongly inclined 

 strata, running north-east, south-west, following the general 

 course of the devonian and silurian strata of the country ; so 

 that the projection of the different constituent strata forms 

 a succession of rather unequal parallel bands which intersect 

 the valley of the Dill. These beds belong to the bluish clay- 

 slate, alternating with some calcareous beds, and form the 

 principal mass of the formation ; but they are interrupted 

 by large masses of greenstone, whicli are most frequently 

 inserted conformably to the planes of stratification, and shew 

 themselves with all their rocks annexed. These annexed 

 rocks are the red clay-slate, whicli represents tlie fir.st de- 



