INFLUENCE OF INDUSTRIAL DEVELOPMENT 347 



There is no doubt that the opinions expressed by Hansen and 

 Ammon have been widely influential in Germany and have 

 stimulated interest in the agrarian policies carried out in that 

 country. Militaristic writers, and we must count Hansen and 

 Ammon among them, have viewed with much concern the 

 relatively poor showing which cities have made according to 

 recruiting statistics and the records of urban birth rates. In 

 numerous German discussions of the subject that appeared before 

 the Great War we find frequent allusion to the "Wehrkraft" or 

 " Wehrfahigkeit," which it was feared might not retain its relative 

 superiority in face of the portentous fecundity of the Slavic 

 neighbors of the empire. The situation which has called forth so 

 many lamentations from Germany obtains to almost as great 

 an extent in most other civilized countries, although its military 

 aspect has caused much less uneasiness. The questions raised by 

 Hansen and his followers are of the most serious consequence to 

 mankind in general, and it should constitute a part of the program 

 of institutions dealing extensively with vital statistics to collect 

 the data required for their solution. 



The views of Hansen, Ammon and their followers have elicited 

 a great deal of adverse criticism on a number of points. The fact 

 urged by Kuczynsky that cities often have a fairly high birth 

 rate and a death rate lower than that of the country is by no 

 means a proof that cities are self-perpetuating. Weber cites as 

 a fatal objection to Hansen's theory the circumstance that in 

 Germany "in several years the ratio of births to deaths has been 

 larger in the great cities than in the Empire as a whole, and in 

 recent years the two ratios have been about the same." It is, 

 however, only an apparent paradox to say that a surplus of births 

 over deaths does not indicate that city populations are self-per- 

 petuating. The immigration of people from 20-40 years of age 

 reduces the death rate and tends to increase the birth rate. How 

 much of the urban increase is due to the fecundity of immigrants 

 from the country is not known. A very considerable part of the 

 population of cities, and a larger proportion of the population of 

 large cities, according to the principle announced by the statisti- 



