2 9 o POPULAR SCIENCE MONTHLY. 



Thirty years ago lay observers began to note differences in 

 central France between the people of the mountains and of the 

 plains. As early as 1868 Durand de Gros noted that in Aveyron, 

 one of the southern departments lying along the border of a 

 mountainous area, the populations of the region thereabout were 

 strongly differentiated. On the calcareous plains the people were 

 taller, of light complexion, with blue or blue- grayish eyes and 

 having fine teeth. In the upland areas, of a granitic formation, 

 the people were stunted, dark in complexion, with very poor teeth. 

 These groups used distinct dialects. The peasants differed in 

 temperament. One was as lively as the other was morose. One 

 was progressive, the other was backward in culture, suspicious of 

 innovations. This same observer noted that the cattle of the two 

 regions were unlike. On the infertile soils they were smaller 

 and leaner, differing in bodily proportions as well. He naturally, 

 therefore, offered the same explanation for the differences of 

 both men and cattle namely, that they were due to the influences 

 of environment. He asserted that the geology of the districts 

 had affected the quality of the food and its quantity at the 

 same time, thereby affecting both animal and human life. When 

 this theory was advanced, even the fact that such differences ex- 

 isted was scouted as impossible, to say nothing of the explanation 

 of them. As late as 1889 I found a German geologist, in igno- 

 rance of the modern advance of anthropology, strongly impressed 

 by these same contrasts of population, and likewise ascribing 

 them to the direct influence of environment as did the earlier 

 discoverer. These differences, then, surely exist even to the un- 

 practiced eye. We must account for them ; but we do it in an- 

 other way. The various types of population are an outcome of 

 their physical environment. This has, however, worked not di- 

 rectly but in a roundabout way. It has set in motion a species of 

 social or racial selection, now operative over most of Europe. 

 This process it is our province to describe in this paper. 



Before we proceed to study the French people, we must cast 

 an eye over the geographical features of the country. These are 

 depicted in the accompanying map, in which the deeper tints 

 show the location of the regions of elevation above the sea level. 

 At the same time the cross-hatched lines mark the areas within 

 which the physical environment is unpropitious, at least as far 

 as agriculture the mainstay of economic life until recent times 

 is concerned. 



A glance is sufficient to convince us that France is not every- 

 where a garden. Two north and south axes of fertility divide it 

 into three or four areas of isolation. These differ in degree in a 

 way which illustrates the action of social forces with great clear- 

 ness. Within these two axes of fertility lie two thirds of all the 



