304 M. B. Studer on the Origin of Granite. 



is clearly declared. In that notice, the metamorphosis of se- 

 condai'}' slates into mica-slate and gneiss, was, perhaps for 

 the first time suggested, not as a theoretical view, but as an 

 ascertained fact ; in the same way as Von Buch had previously 

 proved the transformation, in nature itself, of limestone into do- 

 lomite. In our tour through Glarus, we happened to pass into 

 a part of the mountains where this metamorphosis is exhibited 

 in a more striking way, perhaps, than in any other part of 

 Europe, — where, on the extended sides of the mountain, the 

 eye can, at a glance, follow the whole of the changes, from 

 the greyish-black of the Glarus-^loXe, through violet and 

 purple to the brightest red ; and from the light grey of the com- 

 mon limestone to the brightest straw- yellow of the dolomite, 

 — where, on the Kdrpfstock, even a still higher degree of trans- 

 formation appears, as we find the strata have now become 

 particoloured and shining, containing quartz masses, which 

 include druses of rock-crystal, felspar, garnet, and hornblende, 

 — until, finally, we find ourselves surrounded with rocks such 

 as we observe at St Gothard and in Chamounix. This is 

 so much the more remarkable, because it was in the black 

 slate quarries of Matt, at the foot of these mountains, that 

 the slate containing fossil fishes was first observed as the 

 predominant rock of the bottom of the valley, and also be- 

 cause, on the southern declivity, as we descend from the 

 Kdrpfstock, to the Bind valley, the common Fhjsh soon again 

 presents itself in great thickness among the variegated rocks. 

 I shall here take the liberty of quoting the following sen- 

 tence of a letter which M. Elie de Beaumont did me the 

 honour of addressing to me in August 1838, with the pur- 

 pose of adducing it as an invaluable testimony as to the cor- 

 rectness of our views ; " I have particularly examined," writes 

 the distinguished French geologist, " both during the past 

 year and the present, the environs of Spitzmeileti and Murts- 

 chenstock^ and, with much pleasure, have recognised all that 

 you described some twelve or fifteen years ago, in a me- 

 moir which I requested the editor of the Annates des Sciences 

 to translate and publish in French. You have there sig- 

 nalized one of the most curious and most evident instances of- 



