Page:A Treatise on Geology, volume 1.djvu/223

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CHAP. VI.
MESOZOIC STRATA.
207

in Normandy, about St. Lo: a much larger area lies between the Ardennes and the Vosges, running westward from Luxemburg to Florenville, northward to Witlich and Vlanden, southward to Thionville, Pont-à-Chaussy, Château Salins, and Vic (where rock salt occurs), Mirecour, Jussy, and Villersexel; eastward to Treves, Wadern, Kaiserslautern, Neustadt, Weisspenbourg, Weshoffen, St. Diey, &c. In this large and intricate tract, the hunter sandstein, muschelkalk, and keuper, are fully developed: there are some magnesian bands in the keuper, but no zechstein below the red sandstone. The Vosges are almost wholly surrounded by these rocks.

In like manner the Black Forest is principally surrounded by saliferous deposits, continuously so on the eastern side, from which spreads to the north and east an enormous area of the red rocks, which represent the bed of a sea ramifying in several directions, among islands and promontories of older, and slopes of newer, rocks. The principal part of the mass lies to the east of a long line drawn nearly north from Waldshut on the Rhine, to Minden on the Weser, including the Odenwald, Spessart, and Habichtwald. Portions run out eastward towards Osnaburgh. From Waldshut, by Stutgard, to Dietfurt, nearly parallel to the Danube, is the south-eastern boundary: it thence turns northwards to the Maine, and returns to the Danube at Ratisbon, and fills the narrow space between the Franconian oolites and the primary igneous rocks of the Bohemian border and Thuringerwald. Round the end of these latter mountains it bends to the east, fills all the space between the Harz and the grauwacke border of the Erzgebirge, arid passes the end of the Harz in a long tongue between Magdeburg and Brunswick. (In this enormous area, the zechstein, or magnesian limestone, is exhibited along the Thuringerwald, in Hesse Cassel, on the southern and eastern sides of the Harz, between the Elster and the Saale, and about Waldeck.) The muschelkalk occupies extensive areas, on a line from Waldshut