the village of Suria, a sandstone, which slightly effervesces with acids, makes its appearance. This rock constitutes the sides of the valley which contain the fossil salt.
The immediate vicinity of the salt mines shews no other rock than a yellowish grey sandstone much charged with scales of mica.
We find thus that the salt rock of Cardona is accompanied by clay and sandstone, like our Cheshire salt formation. Limestone also is found near it; but the usual concomitant gypsum appears to be wanting, as well as foetid limestone. The great compactness and purity of this salt merits examination.
Though the country around Cardona is mountainous and rugged, it is inferior in elevation to the districts between it and the Mediterranean; as well as to those which bound it on the north. Immediately behind Cardona the mountains begin to ascend with increasing boldness until they unite with the grand chain of the Pyrenees.
I relinquish to others the difficult task of giving a probable explanation of the formation of rock salt; contented if my observations on the mine of Cardona can add any thing to the mass of facts which should guide us in the obscure but captivating speculations of geology.
