This phenomenon, unique in American history, is to be explained only by three causes, all active in the case of congested Ireland,--a decaying agriculture, lack of communications, and the absence of varied industries.

During the decade from 1860 to 1870 the great Civil War was fought out.

Yet, despite the terrible waste of life and capital in that war, especially at the South, the Northern State of New Hampshire, peopled by the energetic English adventurers who founded New England, was actually the only State which came out of the contest with a positive decline in population.

Virginia (including West Virginia, which seceded from that Commonwealth in 1861) rose from 1,596,318 inhabitants in 1860 to 1,667,177 in 1870.

South Carolina, which was ravaged by the war more severely than any State except Virginia, and upon which the Republican majority at Washington pressed with such revengeful hostility after the downfall of the Confederacy, showed in 1870 a positive increase in population, as compared with 1860, from 703,708 to 705,606.