ANNOTATIONS AND ADDITIONS. 85 



and of latitude. Would not the climate of Germany be 

 wonderfully altered, and that perhaps for centuries, if there 

 were opened a fissure a thousand fathoms in depth, reach- 

 ing from the shores of the Adriatic to the Baltic ? If in 

 the present condition of our planet, the stable equilibrium of 

 temperature, first calculated by Fourier in his Theorie ana- 

 lytique de la chaleur, has been almost completely restored by 

 radiation from the earth into space; and if the external atmo- 

 sphere now only communicates with the molten interior through 

 the inconsiderable openings of a few volcanoes, in the earlier 

 state of things numerous clefts and fissures, produced by the 

 frequently recurring corrugations of the rocky strata of the 

 globe, emitted streams of heated air which mingled with the 

 atmosphere and were entirely independent of latitude. Every 

 planet must thus in its earliest condition have for a time 

 determined its own temperature, which afterwards -becomes 

 dependent on the position relatively to the central body, the 

 Sun. The surface of the Moon also shows traces of this 

 reaction of the interior upon the crust. 



( 11 ) p. 14. " The mountain declivities of the southern 

 part of Mexico" 



The greenstone in globular concretions of the mountain 

 district of Guanaxuato is quite similar to that of the Franco- 

 nian Fichtel-Gebirge. Both form grotesquely shaped sum- 

 mits, which pierce through and cover the transition argilla- 

 ceous schists. In the same manner, pearl stone, porplryritic 

 schists, trachyte, and pitch-stone porphyry, constitute rocks 

 similar in form in the Mexican mountains near Cinapecuaro 

 and Moran, in Hungary, in Bohemia, and in Northern Asia. 



