In the history of a nation or a people there are sometimes important changes taking place, so gradually and quietly that they are scarcely perceptible at the time. It may require a series of years or several generations to work out the problems involved, but they may be followed with results of great magnitude.Some changes of this character have been taking place in our New England population, which we purpose here briefly to notice. In the earlier history of New England there were few changes in the residence of her people. As agricultural pursuits constituted their principal occupation, the same farms and lands continued to a great extent in the same families from generation to generation. Prior to the Revolutionary War very little emigration took place out of New England. In the early part of the present century many persons removed to New York and some to Ohio. From 1810 to 1830 this emigration continued steadily to increase, not only to those States but to the States and Territories farther west. To such an extent had this emigration been carried on that, in 1840, the United States census reported nearly half a million of persons born in New England who were living in other States...