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<l In the Saxon Erzgebirge 3 , says Jame-<e son, we observe the oldest gneiss covered“ by clay-slate, which contains beds of flinty“ slate, greenstone, limestone, and por-“ phyry; over these rests, in a conformable“ position, newer granite, which alternates“ with sienite, gneiss, and porphyry.”
Analogous observations have been made,in the Alps, by Ebel, Escher, and Saussure ;in the ThuringianForest, by Heim; in Scot land and its Islands, by Prolessor Jameson,and Dr. MacCullocb.
I had occasion some time since to visit LesTrois Couronnes, situated on the north east-ern frontier of Spain . This mountain iswell known: Mina was encamped upon itduring the late war, and it has been, inearlier periods, repeatedly the scene of im-portant events, both military and political:from the boldness of its out-line, and itsproximity to the sea, this mountain formsone of the most conspicuous objects on theeastern side of the Pyrenees .
Ascending from the ferry over the Bida-