averaging 73 1/3 persons to the square mile.  Why may not our country at some time average as many?  Is it less fertile?  Has it more waste surface by mountains, rivers, lakes, deserts, or other causes?  Is it inferior to Europe in any natural advantage?  If, then, we are at some time to be as populous as Europe, how soon?  As to when this may be, we can judge by the past and the present; as to when it will be, if ever, depends much on whether we maintain the Union.  Several of our States are already above the average of Europe 73 1/3 to the square mile.  Massachusetts has 157; Rhode Island, 133; Connecticut, 99; New York and New Jersey, each 80.  Also two other great States, Pennsylvania and Ohio, are not far below, the former having 63 and the latter 59.  The States already above the European average, except New York, have increased in as rapid a ratio since passing that point as ever before, while no one of them is equal to some other parts of our country in natural capacity for sustaining a dense population.

Taking the nation in the aggregate, and we find its population and ratio of increase for the several decennial periods to be as follows: 

Year — Population — Ratio of increase.

- — Per cent.

1790 - 3,929,827 - ..........

1800 — 5,304,937 — 35.02

1810 — 7,239,814 — 36.45

1820 — 9,638,131 — 36.45

1830 — 12,866,020 — 33.49

1840 — 17,069,453 — 32.67

1850 — 23,191,876 — 35.87

1860 — 31,443,790 — 35.58

This shows an average decennial increase of 34.60 per cent in population through the seventy years from our first to our last census yet taken.  It is seen that the ratio of increase at no one of these seven periods is either 2 per cent below or 2 per cent above the average, thus showing how inflexible, and consequently how reliable, the law of increase in our case is.  Assuming that it will continue, it gives the following results: 

Year — Population

1870 — 42,323,341

1880 — 56,967,216

1890 — 76,677,872

1900 — 103,208,415

1910 — 138,918,526

1920 — 186,984,335

1930 — 251,680,914

These figures show that our country may be as populous as Europe now is at some point between 1920 and 1930—­say about 1925—­our territory, at 73 1/3 persons to the square mile, being of capacity to contain 217,186,000.

And we will reach this, too, if we do not ourselves relinquish the chance by the folly and evils of disunion or by long and exhausting war springing from the only great element of national discord among us.  While it can not be foreseen exactly how much one huge example of secession, breeding lesser ones indefinitely, would retard population, civilization, and prosperity, no one can doubt that the extent of it would be very great and injurious.