of Serpentine, Sfc. in the Apennines. 169 



metres [about 8 in.], and often reduced into thin strata, and 

 almost laniinje of from three to four centimetres [little more 

 than 1 in.] thick; these beds, highly inclined from N.E. to 

 S, W. or nearly so, are generally straight, parallel to each other, 

 pf greater thickness at the upper portions near the diallage 

 rock; very thin and then a little sinuous below near the 

 cape terminating the mountain. They are perfectly distinct, 

 being uncovered throughout a great part of their extent, and 

 concealed only in a few points by some patches of turf. 

 • This mountain, which is rounded while mounting the 

 torrent of Suvero, beyond the village of Rochetta, shews on 

 that side absolutely the same rocks, and in the same position. 

 It is seen, as well as in the portion I have just described, 

 that the diallage rock of a red paste is always that which 

 touches the jasper; which seems to indicate that it owes its 

 colour to the same cause as that rock, and that it is very 

 nearly of the same epoch of formation as this jasper. 



The mountain (fig. 2), on the left bank of the torrent of 

 Cravignola, bears the name of Montenero, and appears to 

 be the foot or base of that which was shewn us by the name 

 Mont Silva. It is not less steep than that on the right side, 

 and being like it perpendicular at its base, it shews clearly 

 its interior structure, and affords precisely the same series of 

 rocks. The jasper, which is here a little more compact, 

 and the same varieties of diallage rock, occur in the same 

 positions. 



But continuing to mount the torrent of Cravignola, and 

 penetrating as it were into the interior of the mountain, we 

 ought to be able to see, in consequence of the inclination of 

 the beds, the rocks situated beneath the jasper, and conse- 

 quently beneath the diallage rocks and serpentines ; and, 

 in fact the jasper suddenly ends opposite the confluence of 

 the Suvero and Cravignola, and we see : 



4thly. Alternating beds of a soft and very friable schistose 

 rock (E), and a compact limestone (D), succeeding the 

 jasper without interruption, and whose stratification is en- 

 tirely parallel to it, as represented fig. 1. pi. 1. The friable 

 schistose rock is not a primitive argillaceous schist, in the 



