466 POPULAR SCIENCE MONTHLY, 



capable of as great precision as any of tlie other natural sciences. 

 It has humanized geography, so to speak, even as M. Guyot did in 

 his time and generation ; and it has enriched history and sociology 

 in a new and unexpected way. 



Historians have of late shown a distinct tendency toward a 

 fuller appreciation of the importance of physical environment in 

 human affairs.* The movement is probably at one with the 

 newer conceptions of the pre-potency of social over political fac- 

 tors in the making of history. At all events, geography and his- 

 tory have been drawing nearer to one another under the distin- 

 guished leadership of the authors of The American Common- 

 wealth, and of The Norman Conquest of England in the Old 

 World. In America our own Justin Winsor has contributed man- 

 fully to the same end. We have now to bring still other elements 

 anthropology and sociology into touch with these other two, 

 to form a combination possessed of singular suggestiveness. It 

 affords at once a means for the quantitative measurement of 

 racial migrations and social movements ; and it yields a living 

 picture of the population the raw material in and through 

 which all history must of necessity work. Studing men as merely 

 physical types of the higher animals, we are able to trace their 

 movements as we do those of the lower species ; we may correlate 

 these results with the physical geography and the economic char- 

 acter of the environment ; and then, at last, superpose the social 

 phenomena in their geographical distribution. We attempt to 

 discover relations either of cause and effect, or at least of paral- 

 lelism and similarity due to a common cause which lies back 

 of them all perhaps in human nature itself. Anthropology, 

 geography, sociology, correlated and combined, such is the effect. 



Our study thus overlaps several fields of investigation which 

 have stood quite remote from one another in the past ; yet it 

 draws its material from each, and then returns it again endowed 

 with a new and living significance. Some one has rightly said 

 that many great advances in human knowledge have been due 

 to those who effected new combinations of ideas by bringing to- 

 gether results from widely separated sciences. Helmholtz stands 

 as a great modern example, physiologist, mathematician, natural 

 philosopher. Goethe, Spencer, and many more could be cited as 

 well in defense of the same proposition. Science advances by the 

 revelation of new relationships between things. In the present 

 case the hope of perhaps striking a spark, by knocking these 

 divers sciences together, has induced men to collect materials, 

 often in ignorance of the exact use to which they might be 



* For a full discussion of this topic, reference may be made to a paper by the author in 

 he Political Science Quarterly, vol. x, p. 636. 



