592 POPULAR SCIENCE MONTHLY. 



directly to the sphere of natural science. The anthropologist and 

 sociologist alike are called upon to take cognizance of the same phe- 

 nomena. The physical and social sciences are equally involved 

 in the determination of their laws. Certain problems of city life 

 are foremost among these questions, which lie on the border line be- 

 tween what were once widely separate sciences.* 



The most conservative societies in Europe are really to-day a 

 seething mass of moving particles, viewed with the statistical eye. 

 To borrow a familiar figure, a great population almost anywhere 

 is like the atmosphere; even when apparently most quiescent, in the 

 sunlight of investigation, revealing itself surcharged with myriad 

 motes in ceaseless agitation. These particles, microscopic or human, 

 as the case may be, are swept along in currents, determined both 

 in their direction and intensity by definite causes. With men, the 

 impelling forces are reducible mainly to economic and social factors. 

 Most powerful of these movements of population to-day is the con- 

 stant trend from the rural districts to the city. Its origin is per- 

 fectly apparent. Economically it is induced by the advantages of 

 co-operation in labor; perhaps it would be nearer the truth to say, 

 by the necessity of aggregation imposed by nineteenth-century 

 industrialism. This economic incentive to migration to the towns 

 is strengthened by the social advantages of urban life, the attrac- 

 tions of the crowd; often potent enough in themselves, as we know, 

 to hold people to the tenement despite the opportunity for advance- 

 ment, expansion, or superior comfort afforded elsewhere outside the 

 city walls. The effect of these two combined motives, the economic 

 plus the social, is to produce a steady drift of population toward 

 the towns. This has a double significance. It promises to dis- 

 solve the bonds of geographical individuality nay, even of nation- 

 ality; for a political frontier is no bar against such immigration, 

 provided the incentive be keen enough. At the same time it 

 opens the way for an upheaval of the horizontal or social stratifi- 

 cation of population; since in the city, advancement or degrada- 

 tion in the scale of living is alike possible, as nowhere else in the 

 quiet life of the country. 



The sudden growth of great cities is the first result of the phe- 

 nomenon of immigration which we have to note. "We think of this 

 as essentially an American problem. We comfort ourselves in our 

 failures of municipal administration with that thought. This is a 

 grievous deception. Most of the European cities have increased in 

 population more rapidly than in America. Shaw has emphasized 



* All footnote references in this article run to a Bibliography of the Anthropology and 

 Ethnology of Europe to be published by the Boston Public Library. Full titles of all 

 papers will be found under the proper authors and dates in that list. 



