676 THE POPULAR SCIENCE MONTHLY. 



of the Gulf of Mexico. The last civilization was in the course of 

 radiation and transformation when the Europeans came to America, 

 and was wholly independent and autonomous ; but, weak and relative- 

 ly new, it was not able to resist the sudden onset of a stronger race. 



Toward the center of the space whose extremes we have marked 

 out must be placed two other centers of civilization, more ancient 

 than either of the two already named, and in the same zone of lati- 

 tude Egypt, in the valley of the Nile, and near the Arabian Gulf, 

 and Mesopotamia, near the head of the Persian Gulf. Thus, each 

 continental mass had its particular center of civilization, except Asia, 

 which had two one in the extreme east, the other near the line which 

 joins it to Europe. This peculiar grouping of the chief centers of 

 civilization in such a relation of neighborhood constitutes the most 

 considerable paheoethnic fact that we are able to record. The Nile and 

 the Syrian sea on the west, upper Armenia and the Caspian on the 

 north, the Hindoo-Koosh and the Indus on the east, and the Arabian 

 Sea on the south, bound the region where Cushites, Semites, and Ar- 

 yans, the first farmers, workers, and founders of cities, the second pas- 

 toral people, and the third mountaineers, afterward emigrants and con- 

 querors, met, elbowed each other, and mingled, conquerors and con- 

 quered by turns, inventing arts and the use of metals, learning arms 

 and how to organize themselves hierarchically, reaching their ideal 

 through religion, and having in writing the most powerful instrument 

 at the disposition of human intelligence. With them we have the 

 beginning of history, and a continuous chain of social organizations, 

 down to our own days. The growth of civilization in these centers 

 leaves, however, still unaccounted for the diffusion of mankind all over 

 the earth, which took place at a period far anterior to it. 



The spread of man throughout Europe and Asia does not offer 

 very great difficulties, for, in consequence of the long distance for 

 which the two continents are joined, Europe is in reality only a de- 

 pendency of Asia ; and occupation of Europe from Asia is conforma- 

 ble to religious traditions. The difficulties are, however, formidable 

 when we come to America, which we' find occupied from one end to 

 the other by races whose unity has struck the best observers. Not 

 only, moreover, did the American man inaugurate on the soil of the 

 New World an original and relatively advanced civilization, but he 

 has left, chiefly in the north, indisputable traces of his presence in the 

 most remote ages. Pala3olithic implements have been found in the 

 valley of the Delaware, at Trenton, New Jersey, and near Guanajuato 

 in Mexico, so clearly characterized that they can not be mistaken, the 

 situation of which at the base of the Quaternary alluvions and their 

 coexistence with elephants and mastodons, indicate the existence of a 

 race contemporaneous with that of the gravels of the Somme, having 

 the same industry and doubtless the same manners and physical traits. 

 Whence could this primitive American race, sister to the one that lived 



