633 



difficulties in both hemispheres : these masses, 

 of which the forms are very irregular, display 

 traces every whereof great commotions. They 

 are scarcely ever covered by independent forma- 

 tions ; and after having long been believed on 

 the continent of Europe, that gem-salt was ex- 

 clusively peculiar to alpine and transition lime- 

 stone, it is now still more generally admitted, 

 either from reasonings founded on analogies, 

 or from suppositions on the prolongation of the 

 layers, that the real position of gem-salt is 

 found * in variegated sandstone (bunte sand- 

 stein). Sometimes gem-salt appears to oscil- 

 late from variegated sandstone towards mus- 

 chelkalk. 



I made two excursions on the peninsula of 

 Araya. In the former, I was inclined to con- 

 sider the muriatiferous clay as subordinate to 

 the agglomerate (evidently of tertiary forma- 

 tion) of Barignon and of the mountain of the 

 castle of Cumana, because a little to the north 



* See Kleinschrod, in Leonh. Taschenb. 1821, Vol. i, p. 

 148. Humboldt, Essai geogn. p. 271. Hansmann, Jungers 

 Flozgeb., p. 177. Perhaps the gem-salt oscillates from 

 variegated sandstone, at the same time towards alpine lime- 

 stone (zechstein), and towards muschelkalk. An excellent 

 geognist, M. Oeyhausen, places it in the lower layers of 

 muschelkalk. (Karsten, Archiv., 1824, St. 8, p, 11). See 

 also MM. de Decker, Oeyhausen, and la Roche in Hertha, 

 B.l, p. 27. 



