AMERICAN MINES. CHAP. XXI. 



the soil. Labourers were easily procured for the 

 mines by the assistance of the native caciques, who 

 were always ready to send their vassals to the 

 spots where mines were opened, who either worked 

 below the surface for the metals, or cultivated 

 the land to raise food for those who performed 

 that labour, whilst their hereditary superiors drew 

 some gain to themselves from the employment of 

 those of their respective clans. Humboldt asserts 

 that in the time he visited Mexico the work of 

 the mines was executed alone by free labourers, 

 and the knowledge obtained since a more con- 

 stant intercourse has been admitted confirms the 

 assertion. 



Whatever the health and strength of those 

 natives of Mexico who inhabited the moist and 

 sultry plains may have been, it seems that those 

 who live on the elevated levels are far better 

 adapted for severe labour, and far more capable of 

 enduring continued exertion, than any of the 

 tribes that have been carried from Africa to 

 America. The burdens these men are now in 

 the habit of carrying on their backs up a steep 

 ascent from the bottom of the deepest mines to 

 the surface excite surprise in Europe, where 

 such labour is almost exclusively performed by 

 machinery. " The Indians, Tenateros" says 

 Humboldt, " who maybe considered as the beasts 

 of burden of the mines of Mexico, remain loaded 

 with a weight of from two hundred and fifty to 



