IS 
rivers, and partial inundations have pre- 
sented powerful obstacles to the migration 
of nations. The extensive countries of the 
north of Asia are as thinly peopled, as the 
t 
savannahs of New Mexico and Paraguay ; 
>• 
nor is it necessary to suppose, that the coun- 
tries first peopled are those, which offer the 
greatest mass of inhabitants. The problem 
of the first population of America is no 
more the province of history, than the 
questions on the origin of plants and ani- 
mals, and on the distribution of organic 
germs, are that of natural science. His tory, 
in carrying us back to the earliest epochas, 
instructs us that almost every part of the 
Globe is occupied by men who think them- 
selves aborigines, because they are ignorant 
of their origin. Among a multitude of 
nations, who have succeeded, or have been 
incorporated with each other, it is impos- 
sible to discover with precision the first 
basis of population, that primitive stratum 
beyond which the region of cosmogonical 
tradition begins. 
i 
