June 5, 1903.] 



SCIEXCE. 



891 



The populations for the extreme or 

 latest points on the curve are given above : 



Likewise there is given with the above 

 table the present rate of increase in popu- 

 lation per decade; there is also stated the 

 special features of each city — its area, 

 density, etc. 



As to density of population, this is 

 shown graphically by squares on the 

 diagram. 



The comparisons in figures are as fol- 

 lows : 



New York. — Maximum density, 630,740 

 per square mile on 3.6 acres. Average 

 maximum density, 480,000 per square mile 



Philadelphia. — Average density, 8,091 

 per square mile, area 129 square miles. 



Chicago. — Average density, 8,430 per 

 square mile, area 186 square miles. 



The data for density were obtained about 

 1894. 



A prediction is made of the population 

 of each city in 1910 and 1920, taking into 

 consideration important factors which are 

 likely to change the present rates of in- 

 crease, such as, first, the changes which new 

 methods of transportation may bring about, 

 either taking people more quickly and 

 cheaply into cities, or out of them into more 

 distant districts now open areas or sparsely 



The Author's 



Estimated 



Population 



for 1900. 



Actual 



Population, 



1900. 



Estimated 



Population 



in 1910. 



Estimated 



Population 



in 1920. 



Greater London .... 



London 



New York (Greater 



Paris 



Greater Paris 



Berlin 



Greater Berlin 



*Greater Chicago . . . . 



Philadelphia 



St. Petersburg 



6,496,000 

 4,599,800 

 3,900,000 



2,697,300 



2,101,400 



2,400,000 

 1,414,500 

 1,185,600 



6,652,145 

 4,589,129 

 3,833,999 



1901 

 2,660,559 

 3,599,991 

 1,884,157 

 2,512,523 

 1,838,735 

 1,369,632 

 1,132,677 



1897 



7,490,400 

 4,967,784 

 4,953,000 



2,967,030 

 4,139,990 

 2,731,820 

 2,914,517 

 2,574,229 

 1,697,400 

 1,339,728 



8,516,256 

 5,315,528 

 6,191,250 



3,234,063 

 4,759,589 

 3,496,729 

 3,322,549 

 3,475,209 

 2,002,932 

 1,500,495 



on 320 acres. Average density. New York 

 city proper, 40,000 per square mile on 37 

 square miles. 



London. — Maximum density, 132,000 per 

 square mile on 357 acres. Average density 

 (registration London), 37,000 per square 

 mile on 117 square miles. 



Pans.— Average density, 79,300 per 

 square mile on 31 square miles. 



St. Petersburg.— Maximum density, 227,- 

 276 per square mile. Average density, 

 28,260 per square mile on 35 square miles. 



JSerlm.— Maximum density, 92,600 per 

 square mile. Average density, 67,612 per 

 square mile, area 23.4 square miles. 



* Chicago. The erroneous estimates of popula- 

 tion in 1894 require revision of prediction. 



settled country. Second, the congesting' 

 or overcrowding of city areas, making them 

 too dense for comfort or health. These 

 two conditions are already producing 

 changes of magnitude in population. Lon- 

 don is an instance of these effects, or of 

 some others possibly ; several of the central 

 districts, instead of showing an increase, 

 showed actual decrease in the last two 

 census epochs. 



It is difficult to predict now what change 

 will take place in New York during the suc- 

 ceeding decades by the contemplated trans- 

 portation changes; such as the opening of 

 the new bridge over the East River, prob- 

 able completion of the old Hudson River 

 tvmnel, the construction of the Rapid 



