E. MINERALOGY AND GEOLOGY. 99 



r 



the body of the earth, basing this impression upon the fre- 

 quent coincidence of violent disturbances of the magnetic 

 needle with earthquake shocks. This view is corroborated 

 by a recent communication of Professor Sumichrast, an emi- 

 nent naturalist residing in Mexico, who expresses the opinion 

 that it will not be far from the truth to state that the major- 

 ity of earthquakes experienced in Mexico are due to magnetic 

 agencies rather than volcanic, the concurrent deviation of the 

 magnetic needle, the sudden heating of the atmosphere, etc., 

 seeming to point to magnetic action. 



PHYSICAL PHENOMENA IN ECUADOR. 



In a recent report of the governor of the province of Leon 

 to the general government of Ecuador, it is stated that in 

 February, 1869, noises were heard on the mountains of the 

 Western Cordilleras in the vicinity of Cotopaxi, and that 

 immense masses of earth and rock were thrown out, while 

 springs of water burst forth in such quantity that the rivers 

 were overflowed and much damage done, the phenomena be- 

 ing unaccompanied, however, by earthquakes. The climate, 

 too, seemed to have become much hotter than previously, 

 many kinds of plants having flowered that had never done so 

 before, and the sugar-cane being fit to cut in twenty-four 

 months instead of thirty. Since 1869 the springs have all 

 dried up, and the volcano has become inactive, and from these 

 indications it is feared that a new disturbance is breeding; 

 which may produce great damage on breaking out. Panama 

 Star and Herald, June 1, 1871. 



GEOLOGY OF THE ALPS. 



Les Mondes for October 5 coutains elaborate articles by 

 Elie de Beaumont and Sismondi upon the geology of the 

 Alps, in connection with the Mont Cenis Tunnel, in which full 

 details are given of the structure of this mountain chain, and 

 of the history of the enterprise connected with its perforation. 



In regard to the geology of the Alps, Mr. Sismondi sums 

 up with the following conclusions : first, that the anthracitif- 

 erous rocks of the Alps constitute three groups, differing 

 from each other in the nature of their rocks, in variance of 

 level in their beds, and in the remains of organic substances 

 which they contain ; second, the order in which the rocks 



