that even when there were no wagon roads in Mexico one could travel 

 in a carriage from the City of Mexico to Santa Fe. Baron Humboldt 

 and other geologists considered the cordilleras of Mexico as a portion 

 of the Andes of South America, which originate in Patagonia, extend- 

 ing over the whole of that continent ; but researches were made spe- 

 cially by a corps of engineers, who surveyed Mexico during the French 

 Intervention, arrived at a different conclusion, and consider that the 

 Andes proper end in Panama, and that the Mexican cordilleras are 

 entirely independent from that lofty chain of mountains. 



In contrast with the plains and at times barren districts of the 

 central plateau, it is occasionally broken by depressions of the soil, 

 known as barrancas, descending sometimes one thousand feet and 

 measuring several miles across, which are covered with a luxuriant 

 vegetation of trees and shrubs, and watered by small streams running 

 through the middle of the valley. Among the most remarkable ones are 

 the barranca de Beltran descending the western slope from Guadalajara 

 to Colima, and the barranca de Mochitilte from Guadalajara to Tepic. 



One of the pre-eminently interesting features of Mexico is the 

 mountain of Jerullo, in this section, which has been born within recent 

 times. The natives described to Alexander von Humboldt the con- 

 vulsions of the earth during its birth, and the frightful spectacle of the 

 huge mass thrusting its giant shoulders among its neighbors, making 

 room for itself in their ranks. 



The best way to illustrate the broken surface of Mexico is to give 

 the altitudes of some of the principal localities, both from the coast to 

 the interior and from the interior back to the coast, taken from the 

 measurements made by the railroad companies and by the engineers of 

 the Mexican Government in the national wagon roads where railroads 

 are not yet running. I append to this paper a list of such altitudes, 

 with their distances, whenever I have been able to find them, which 

 I consider the best illustration that could be presented on this subject. 



