POPULATION OF THE UNITED 8TATES 219 



may be made of plateaux and mountain regions. In the census of 1900, 

 this classification was taken up in a brief and supplementary way, and 

 the area, population and density of the several physiographic regions 

 were computed and are placed before the reader. The areas are not 

 exact, for the boundaries had to be determined by the nearest available 

 county lines, but the error can hardly be of disturbing proportions. 



It is not here possible to exhibit or discuss the interesting facts 

 brought out by this new departure of the census. It marks, however, a 

 step of progress in understanding the adjustment of our people to their 

 environment. Under the designation of New England Hills are in- 

 cluded New England, the Adirondacks and the foothill country east of 

 the Hudson in the state of New York. The density for this region 

 is the highest in the United States, 124.1. How strongly population 

 turns on other factors than soil, thus appears, and the result becomes 

 astonishing when we put down in comparison the present density of the 

 prairie region, viz., 29.2. 



Using the new land classification, we may approach again the pos- 

 sible or probable population east of the great plains, or in the well- 

 watered eastern section of the United States. Leaving out the New 

 England Hills, which already exceed the density we are about to pro- 

 pose, and omitting the Appalachian Plateau and the Ozark Hills, it 

 would seem reasonable to expect an average density of 100 for the re- 

 maining territory of the east. This is about the density of Europe. 

 The territory for which we propose it includes the coastal plains and 

 lowlands, the Appalachian Valley, the piedmont and lake regions, the 

 Mississippi alluvial region, the interior timbered region and the prai- 

 ries. One need not apologize for thinking this aggregate physically as 

 good as average Europe. Two of the regions, the Appalachian Valley 

 and the piedmont, already have more than three fourths of the density 

 proposed, and the interior timbered region, so far from being the wilder- 

 ness implied by its name, has a density of 68.7. Eaising the whole to 

 100, we pass from the present 53,800,000 to 127,600,000. If to this 

 total we add the present population of the New England Hills, the 

 Appalachian Plateau and the Ozark Hills, we bring our total to 145,- 

 000,000. If we allow reasonably for the growth of these three regions 

 we place the figure at 150,000,000. 



A density of 100, however, seems a low expectation for the prairies, 

 and also for the lake region, which last already has 55.2 persons per 

 square mile. Considering the soil, climate, minerals and transporta- 

 tion facilities of the lake borders, their population must largely in- 

 crease. Give these two regions the present density of France or of 

 Austria-Hungary, we must add to the total already reached, 40,000,000 

 for the prairies and 15,000,000 for the lakes, bringing our total east of 

 the great plains to 205,000,000. 



Iowa is a typical prairie state and has 55,475 square miles, not 

 counting a few hundred miles of water surface. This state has about 



