THE PROGRESS OF SCIENCE
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The Population of the United States.
population in the United States during the past century seems to indicate a boundless growth. But a different interpretation appears to be possible. The percentage of increase for continental United States was remarkably constant in each decade from that beginning in 1790 to that beginning in 1850. For each period the percentages are as follows: 35.1, 36.4, 33.1, 33.5, 32.7, 35.9 and 35.6. But in the census of 1870 there was a sudden drop in the percentage to 22.6, which is attributed in part to the civil war and in part to defective enumeration. There was a rise in 1880 to 30.1, followed by a fall to 24.9 in 1890 and to 20.7 in 1900. The decrease in percentage from 1860
