5 oo THE POPULAR SCIENCE MONTHLY. 



the inferior than to the superior race. It soon disappears, and 

 gives place to a race which may represent, in a mental respect, a 

 kind of mean between the two races, but morally is inferior to 

 either of them. Half-breeds have never made a society advance ; 

 the part they have played has been to degrade the civilizations 

 of which they have by chance been the heirs. The disastrous re- 

 sults of such mixtures of superior races with inferior were clearly 

 perceived by the most ancient civilized peoples. This was doubt- 

 less the origin of that rule of castes, preventing unions between 

 persons of different races, which we find in many ancient societies. 

 Without it, man would never have risen above the dawn of civili- 

 zation. 



But, while the mixture of races which have reached very un- 

 equal stages of evolution is always disastrous, the result is other- 

 wise when these races, although still possessing different qualities, 

 have arrived at nearly the same period of development. Their 

 qualities can then very usefully complement one another. The 

 republic of the United States has been formed by precisely such a 

 mixture of races, already elevated in civilization and having 

 qualities complementary to one another. The people owes its 

 astonishing vigor to the fact not only that it is constituted of 

 a mixture of elements — English, Irish, French, German, etc. — 

 already highly developed, but also that the individuals through 

 whom the crossing was effected were themselves the results of a 

 selection from among the most active and vigorous members of 

 those nations. 



The general laws which we have just summarized can of them- 

 selves furnish the explanation of a large number of historical 

 events. They show, for example, why one conquest was the origin 

 of a brilliant civilization, and why another introduced an era of 

 disorder and anarchy ; why the Oriental has always easily imposed 

 his yoke and his customs upon Orientals whose mental constitu- 

 tion was like his own ; and why struggles between Orientals and 

 Westerners have been so ferocious, and usually terminated in piti- 

 less massacres of the conquered. They likewise tell us why certain 

 peoples have been colonizers, and how they have been able, natu- 

 rally, if they were of the race of the conquered, or by respecting 

 their customs and creeds if they were of a different stock, to main- 

 tain their authority over distant nations. 



A question has arisen as to whether the steady advance of man 

 tends to equalize races, or to differentiate them more and more. 

 To it we have to answer that the upper level of civilization is 

 always ascending ; but by this fact itself, and since there are 

 always nations at the lowest step, the gulf between them and the 

 higher races is constantly growing deeper. There is progress, it 

 is true, even in the most backward groups. But the law of this 



