1821.] and adjoiiiing Farts of the Continent, 467^ 



be seen also by the road side at Charmey, between St. Michel 

 and the Hospital of Mount Cenis, and also at the Hospita,Lof 

 Mount Cenis. < 



3. Secondary Gi/psum. — Of the same age with the magnesian ; 

 limestone, and new red sandstone formation of England, this is 

 usually misealled transition gypsum by most writers on the Alps, 

 It occurs at Bex and Leisigen in Switzerland ; in the salt mines 

 of Tyrol and Saltzburg ; at Michell, 10 miles north of Trent ; 

 and Lovinio, near Menagio on the Lake of Como. 



4. Fibrous Gi/psum. — Of tertiary formation, of the same age- 

 with the Paris beds occurs in the molasse of Switzerland, 

 near Yverdun ; in Argovie, near Soloure ; at Boudry, near 

 Neufchatel ; and St. Julien, near Geneva. 



Dolomite, Five Kinds. 



In the alpine regions there occur also five formations of dolo 

 mite. 



1. Primitive, — The primitive limestone of the central Alps-' 

 often passes into the state of dolomite, of which a good example 

 may be seen at the pass of Mount Brenner between Botzen and" 

 Inspruck. It is here compact, and interspersed with flakes of 

 talc, of a delicate green colour. The primitive Hmestone alscv 

 which forms the matrix of the great iron works of Eisentertz, in 

 Styria, is in the state of dolomite. This stratum is of great 

 importance and extent in the Alps, and may be traced by its 

 sparry iron ore from Lake Como to Eisenertz, and thence 

 onwards into Hungary. 



2. Transition,-T-i did not find dolomite in the few spots in 

 which I had opportunity to see the transition limestone of the 

 Alps ; but as this formation abounds with magnesia in England, 

 Russia, and North America, it is probable that it requires pnly 

 investigation to find it also in the Alps. 



3. Elder Alpine limestone. — Dolomite prevails in no alpine 

 formation so much as in this, which is equivalent to the grand 

 magnesian limestone of England : it may be usually recognised 

 by its pearly glimmering lustre. The soft powder that fills the 

 cells of the rouhwacke and holen kalkstein is much charged with 

 magnesia: as are also the strata of yellow sandy limestone that 

 lie in the new red sandstone of the Vale of the Adige above 

 Trent. 



In England, much dolomite occurs also in the mountain lime* 

 stone. - , 



4. Younger Alpine Limestone. — Beds of dolomite minutely 

 crystalline, and of pearly glimmering aspect, abound in the oolite 

 formation in the Valley of the Adige below Trent, and also ia 

 the hills on the west of Monte Bolca. In England, magnesia 

 has been found in the oolite formation at Minching Hampton*, 

 near Cheltenham. It occurs also in the chalk of France. 



2g2 



