108 M M. Junker «Sc Dufkenoy 



Tfrt sti^facie at the separation of the two rocks, at least 

 the part that can be observed on the coast, is tolerably re- 

 gular, with the exception of two points which the granite 

 forms ifi the schist, and round which the latter marttles ; it 

 has a direction from N.W. to S.E. 



The fiist rock of this group, composed of iriica and quartz 

 in very variable proportions, occupies a space of about 50 

 metres [164 feel] in the parts nearest the granite ; mica 

 of a golden yellow colour is most abundant, the rock is very 

 soft and decomposed. 



Beyond this, the quartz augments and communicates to 

 the composition its hardness and indestructible character. 

 It is then in some places reddish, in otiiers yellow ; some- 

 times even the quartz is the sole ingredii-nt, apparently 

 without mica, and wthout change in the schistose structure 

 of the rock ; it is on a small scale, only very much contbrted, 

 and contains within its folds nodules of quartz. 



The rock that immediately follows the last is composed 

 of hiica and tourmaline (schorl ?) in very thin needles, cros- 

 sing each other in every direction, and of a little quartz. It 

 is not contorted, and contains veins of quartz and felspar 

 parallel to the laminae. 



The tourmaline (schorl ?) is sometimes so abundant in it, 

 as to form black stripes or veiiis, giving it a ribbon-like 

 structure. 



The third rock, forming the point named the Bichef, is 

 composed of grains of quartz, and crystallized felspar d?s- 

 seminated in a paste of greenish-grey mica ; it sometimes 

 contains in the direction of the laminae veins of quartz, at 

 others of felspar, often swelling out considerably. 



The fourth rock differs from the preceding in no' lonfgei' 

 containing the grains of quartz and felspar ; th6 paste alone' 

 remains, which is of a greenish-grey colour, very soft and 

 unctuous to the touch. 



It is covered by a singular rock, which is a quartz, pos- 

 sessing an imperfectly schistose structure, of a dark black 

 colour, containing between its lamina; a black brilliant sub- 

 stance that strongly soils the fingers, and h probably com- 



