6o8 TRANS. ST. LOUIS ACAD. SCIENCE. 



Year. Computed Population. 



1900 77,472,000 



I91O 94,673,000 



1920 114,416,000 



1930 136,887,000 



1940 162,268,000 



1950 190,740,000 



i960 222,067,000 



1970 257,688,000 



1980 296,814.000 



1990 339'i93-ooo 



2000 : 385,860.000 



2100 1,112,867,000 



2500 11,856,302,000 



2900 40,852,273,000 



These figures are suggestive, to say the least. They show- 

 that within a hundred years the population of this country will 

 amount to 350 millions ; and within a thousand years, if the 

 present rate of growth continues, this number will have swelled 

 to nearly 41 billions. 



How great a change in the conditions of living this growth of 

 population would imply it is, perhaps, impossible for us to real- 

 ize. Great Britain, at present one of the most densely "populated 

 countries of the globe, contains about 300 inhabitants to the 

 square mile. Should the present rate of growth continue until 

 the year 2900, the United States would contain over 11,000 per- 

 sons to each square mile of surface. 



With growth of population our civilization is becoming more 

 and more complex, and the drafts upon the stored energy of the 

 earth more enormous. As a consequence of all this, it would 

 seem that life in the future must be subject to a constantly in- 

 creasing stress, which w^ill bring to the attention of individuals 

 and nations economic questions which at our time seem very 



remote. 



H. S. Pritchett. 



December, 1890. 



