MIGRATIONS OF RACES OF MEN CONSIDERED HISTORICALLY. 571 



during" the last two centuries;, are ou their way to becoiue practically 

 uudistinguisbable from the true Slavonic Russians of Kieif. And, to 

 come nearer home, the Celts of Cornwall have been anglicized, and 

 those of the Highlands of Scotland have in many districts become 

 assimilated to the Lowland Scotch, with no great intermixture of blood. 

 It iswortb wbile to be exact in distinguishing this process of Permea- 

 tion from cases of Dispersion, because tlie two often go together — that 

 is to say, the migration of a certain, though perhaps a small, number 

 of persons of a vigorous and masterful race into a territory inhabited by 

 another race of less force, or iierhaps on a lower level of culture, is apt 

 to be followed by a predominance of the stronger type, or at any rate 

 by such a change in the character of the whole population as leadsmen 

 in later times to assume that the number of migrating persons must 

 have been large. The cases of the Greeks in Western Asia and the 

 Spaniards in the New World are in point. We talk of Asia IMinor as 

 if it had become a Greek country under Alexander's successors, of 

 Mexico and Peru as Spanish countries after the sixteenth century, yet 

 in both instances the native population must have largely prei^onder- 

 ated. If therefore, we were to look only at the changes which the 

 speech, the customs, the ideas, and institutions of nations have under- 

 gone, we might be disposed to attribute too much to the mere move- 

 ment of races, too little to the influences which force of character, 

 fertility of intellect, and command of scientific resource have exercised, 

 and are still exercising, as the leading races become more and more the 

 owners and rulers of the backward regions of the world. 



II. — CAUSES OP MIGKATION. 



We may now proceed to inquire what have been the main causes 

 to which an outflow or an overflow of population from one region to 

 another is due. Omitting, for the present, the cases of small colonies 

 founded for special purposes, these causes may be reduced to three. 

 They are food, war, and labor. These three correspond in a sort of a 

 rough way to three stages in the progress of mankind, the first belong- 

 ing especially to his savage and semi-civilized conditions, the second to 

 that in which he organizes himselfin political communities, and uses his 

 organization to prey upon or reduce to servitude his Aveaker neighbors; 

 the third to that wherein industry and commerce have become the rul- 

 ing factors in his society and wealth the main object of his efforts. The 

 correspondence however is far from exact, because the need of subsist- 

 ence remains through the combative and industrial periods a potent 

 cause of migration, while the love of war and plunder, active even 

 among savages, is by no means extinct in the mature civilization of 

 to day. 



1. In speaking of food, or rather the want of food, as a cause, we must 

 include several sets of cases. One is that in wliich slieer hunger, due 

 perhaps to a drought or a hard winter, drives a tribe to move to some 



