p6 MEXACHAX1TE IN MICACEOUS SCHIST. 



disappear, and are replaced by transition rocks, till we com* 

 to the micaceous schist*. 



I sought in vain for the black sand in the bed of the Va- 

 renna. The pebbles with which it is loaded, and still more 

 the fine sand and clay, which in the alluvions are last depo- 

 sited on the bed of the torrent, do not allow it to be disco- 

 vered. 



I then directed my search to the slope of the mountains, 

 both on the side of Pegii and on that of Sestri; to examine 

 whether mechanite were one of their component parts. 

 Menachanite ]yj v fi rs t discovery of menachanite was in the little wood 

 k^ Grimaldi, above Pegli, on the right of the Varenna, about 



1 kil. [3278 feet] above the level of the sea, and about 100 

 met. [328 feet] from the place where the menachanite had 

 hitherto been found f . 



The night before I observed this a very heavy rain had 



fallen. The streams descending from the mountain had 



furrowed the ground in all directions, and let fall on the 



borders of the furrows the gravel they had washed down. 



On these borders I soon saw the black sand, which had every 



appearance of the menachanite on the shore of Pegli, and 



which was found on examination to be perfectly similar to 



it. 



tr "eTt ^ tnen trace< ^ tms M ac k sand to the beginning of the edge 



distance. of the plain between the foot of the mountain and the sea; 



and no doubt should have been able to trace it to the shore, 



if the cultivation of this plain, and the successive deposits 



of the Varenna, which 1 have already mentioned, had not 



interrupted my search. 



The mountain IV]y next step was to examine with attention the mountain 



examined and on t j lt , back of which I had iust discovered the menachanite. 

 described^. . . ' . 



It is formed of a micaceous schist, of a silvery gray colour, 



composed of thin laminae so tender as to be broken by the 



* The different systems of mountains observed in the Apennines of Li- 

 guria, and every thing that concerns the natural history of this country, 

 will be displayed in my Tours in the Apennines, which will soon appear. 



•f Here is evidently some mistake, pither in the copy, or of the printer. 

 I imagine it should have been -327H feet from the shore, and at 328 feet 

 elevation. C. 



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