Reviews. 



Recent Contributions to the Subject of Dynamometamorphism 



from the Alps. 



A. Heim: Geologie der Hochalpen zwischen Reuss und Rhein. Bei- 

 trage zur geologischen Karte der Schweiz, Vol. XXV., 4 : Bern, 

 1891, pp. 503. 



C. Schmidt: Beitrage zur Kenntniss der auftretenden Gesteine. ib. 

 Anhang, pp. 76. 



L. Milch: Beitrage zur Kenntniss des Verrucano. Erster Theil : Leip- 

 zig, 1892, pp. 145. 



M. P. Termier : Etude sur la Constitution geologique du Massif de la 

 Vanoise. Bull, des Services de la Carte geol. de France. No. 20, 

 Paris, 1891, pp. 147. 



For many years both Huttonian (metamorphic) and Wernerian 

 (original deposition) principles have been advanced to explain the 

 crystalline schists of the Alps, as well as those of other regions. 

 Because of their youth these great mountains are in many ways pecu- 

 liarly fitted to throw light upon the difficult problems presented by 

 these rocks. Many of the most classic Alpine localities are now being 

 investigated by modern methods and are yielding welcome results 

 which tend to establish not merely the fact, but also the nature, cause 

 and processes of metamorphism. 



Nowhere is this more true than in the region of vast earth-move- 

 ments which Professor Heim of Zurich, has made the scene of his life 

 work. As the result of his labors in this field, he was able to publish 

 in 1878 his monograph on the Todi-Windgalle group and the 

 accompanying essay on the Mechanism of Mountain-making — a work 

 which must certainly be regarded as epoch-making in suggesting the 

 clue to a satisfactory explanation of the problems of regional meta- 

 morphism. This book Professor Heim now supplements with another 

 of almost equal size, which contains the explanatory and descriptive 

 text of the remainder of Sheet XIV of the Geological Survey of Switz- 



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