on the Strata of Mont Blanc. 



645 



{Jg- Vl.)) are excellent examples of the pyramidal and 

 splintery formation which these granite ranges in general 

 *71 _^. _ __ ^ \ assume. They rise 



out of immense 

 fields of snow; but, 

 being themselves 

 too steep for snow 

 to rest upon, form 

 red, bare, and in- 

 accessible peaks, 

 which even the cha- 

 mois scarcely dares 



bases appear some- 

 times abutted 

 against (if I may 

 so speak) by mica 

 slate, which forms 

 the south-east side 

 of the Valley of 

 Chamonix ; whose 

 flanks, if inter- 

 sected, might appear as in^. 72. a. Granite, forming on the 

 one side (b) the Mont Blanc, on the other (c) the Mont Breven ; 



bf mica slate resting 



A 



\ 



r^ 



A' -^^ 



on the base of Mont 

 Blanc, and which con- 

 tains amianthus and 

 quartz, in which capil- 

 lary crystals of tita- 

 nium occur; c, calca- 

 reous rock ; d, alluvium, forming the Valley of Chamonix. 

 I should have mentioned that the granite appears to contain 

 a small quantity of gold, as that metal is found among the 

 granite debris and siliceous sand of the river Arve \_Bakewell^ 

 i. 375.] ; and I have two or three specimens in which chlorite 

 (both compact and in minute crystals) occupies the place of 

 mica. — J. R, March, 1834?. 



IRemjrxs, obligingly added by the Rev. W. B. ClarJce, to 

 'whom we had submitted J. R.'s Notes."] 



The granites of the Mont Blanc have already been ably 

 described by various geologists; as Saussure, De Luc, the 

 writer in Ebel, Mr. Bakewell, &c. The latter author has given 

 a coloured view of the Aiguille de Dru as a frontispiece to 



T T 3 



