GLIMPSES OP FEE-HISTORIC TIMES. 



55 



buildings of Central America, Yucatan, and Mexico, 

 there seems the best reason to believe that some of 

 the Mississippi mounds are very ancient. Very old 

 trees were found growing on them, and there were 

 indications of previous generations of trees. The 

 f( garden beds " of extinct and forgotten tribes are 

 found to have extended themselves over the earth- 

 works of earlier people. Professor Swallow, of Mis- 

 souri, informs me that he opened two ancient burial 



Fig. 11. MODERN HAND AIT, AITD ANCIENT AZTEC HEADS. 

 (After Catlin and Wilson.) 



mounds in that State, on which vegetable soil two feet 

 thick had accumulated, and around which six feet of 

 alluvial silt had been deposited, apparently in con- 

 sequence of a subsidence of the soil on which the 

 mound had been built, in some pre-historic earthquake, 

 similar, perhaps, to those which in modern times pro- 

 duced the sunk country of New Madrid in the same 

 region. In the alluvium which had accumulated was 



