272 Prof. Hausmann on the Geographical Characters and 



rocks; granite breaks out on its southern foot towards the 

 Guadalquiver. This rock, so frequent in the Iberian penin- 

 sula, appears to be wanting in the highest southern chain. The 

 middle mountain ridges consist of mica-slate, abounding in gar- 

 nets, which, in the ridges lying before them, passes into less 

 crystaUine mica-slate, chlorite-slate, and clay-slate, which some- 

 times inclose beds at times of vast magnitude, of compact 

 hmestone, marble, dolomite, and serpentine. On the south 

 coast, newer transition-slate and grey wacke-slate, with beds of 

 flinty slate, lie here and there on the older slate. The basis or 

 fundamental rock of the Rock of Gibraltar is of these rocks. 



The structure of the chains of mountain corresponds in gene- 

 ral with their chief direction. Not only the alternations of the 

 different rocks, but also the direction of the strata, are conform- 

 able with the direction of the chains ; hence, in the greater part 

 of Spain, the principal direction of the slaty rocks is from SW. 

 to NE. or WSW. to ENE. But the inclination of the strata 

 varies. In the Pyrenees properly so called, the dip of the 

 strata is conformable with the two acclivities of the range. In 

 the Somosierra and Guadarrama ranges, the principal mass of 

 gneiss dips SE. towards the granite lying before it. In the 

 Sierra Morena, the predominating dip of the slaty strata is to- 

 wards the NW., so that they appear to rest on the granite 

 which breaks from under them. In the Sierra Nevada, the 

 dip of the strata is conformable with the two acclivities of the 

 chain. It is worthy of remark how the curvature of the south 

 coast of Spain obeys the direction of the strata, and how the 

 formation of the far projecting southern point of the land also 

 stands in connection with the direction of the strata. At the 

 foot of the Rock of Gibraltar, the slaty strata run nearly north 

 and south, with a rapid dip towards the east. The Gut of 

 Gibraltar is therefore nearly at right angles to the direction of 

 the strata. The rocky wall between the Mediterranean and 

 Atlantic seas, by this direction of the strata, must have opposed 

 the strongest resistance to the currents. 



The primitive and transition rocks, in very different places, 

 are rich in ores. The present mines are confined principally to 

 the south-west and south-east parts of Spain. The mighty 

 lead-glance veins of Linares occur in granite ; the colossal de- 



