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On the Forms assumed hy Granite and Gneiss at the surface o, 

 the Earth. By Baron Leopold Von Buch. 



In almost every locality where granite occurs, it is quite 

 apparent that the projecting mass forms part of an ellip- 

 soid with a convex surface. This is beautifully seen in the 

 Brocken, when we ascend from Elbingerode by Schierke. 

 These ellipsoids ^re of greater or smaller extent, sometimes 

 many German miles in size, as in the Riesengebirge, in 

 the Bohemian and Moravian mountains, in the Odenwald, in 

 the Black Forest, and in Cornwall ; or only the size of hills, 

 but then they are grouped together in larger numbers, as in 

 the southern part of Hindostan, or in Sweden and Finland. 

 If the granite is covered by gneiss, then the latter follows the 

 form prescribed for it by the granite. In the interior, these 

 convex masses are formed of layers, which lie concentrically 

 over one another, always becoming smaller and smaller, till 

 they form a kind of cylinder of but small breadth. The po- 

 sition of the superimposed mountain rocks, and the change 

 produced at their boundaries by the granite, lead to the very 

 probable conjecture that the granite itself has been raised 

 from the interior like a kind of bladder, and that the rocks 

 covering it have been either pushed aside, or completely con- 

 verted into new rocks. The division into layers was a conse- 

 quence of the cooling of the granite which was raised at a 

 high temperature ; for, the experiments of Gregory Watt, and 

 Gustav Bischoff of Bonn, have directly proved such a laminated 

 separation of cooling masses. The surface of this convex mass 

 of granite is often covered with an inconceivable number of 

 blocks that are not far distant from their parent rocks, which, 

 however, often rise to great heights. So it is on the Brocken, 

 on the Achtermanshbhe, on the Riesengebirge, at many loca- 

 lities in the Black Forest, and almost at every place where the 

 granite is of some extent. These desolate block-covered sur- 

 faces have given rise to the legend of " Devil's Mills" {Teufels 

 Muhten) ; they are also sometimes termed " Rocky seas" (Fet- 

 sen Meere\ and, in Greece, " Devil's floors" (Ulrich's Reise, 

 vol. i., p. 121). They also are results of the contraction y and 

 consequent separation of the cooling surfaces ; and hence it is 



