During the war the production of cotton in the United States had been almost constant in amount and less than in preceding years, but 1815 saw an increase of over forty-two per cent and 1816 an increase of twenty-four per cent,(289) while in the latter year South Carolina, after an interval of thirteen years, resumed its slavery legislation by passing the first of a series of acts which show that the slavery problem was becoming increasingly difficult. Similar legislation took place in Tennessee, and to a lesser degree in Kentucky.(290) Increased production of cotton was accompanied by an increase in price, middling upland cotton selling at New York at 15 cents per pound in 1814, at 21 cents in 1815, at 29-½ cents in 1816, at 26-½ cents in 1817, and at 34 cents in 1818, while South Carolina sea-island cotton sold at Charleston in 1816 at 55 cents a pound.(291) An increase in cotton production meant an increase of the plantation system with its slaves, this meant an increased demand for large farms, and also a strengthening of the antagonism between pro-slavery and anti-slavery parties. Even in 1812, a man who wished to sell, lease, or rent his manufacturing establishment in the northwestern part of Virginia, Frederick county, lamented in his advertisement that “some good men of strict moral or religious principles should object against forming settled abodes in Virginia” or other slave states.(292) Census reports show that the proportion of negroes to whites increased in the western counties of North Carolina during the decade 1810 to 1820 over the proportion in 1800 to 1810. Conditions above described naturally led to the emigration of at least four classes of people: those who were anti-slavery, those who did not wish to change from small farming to the plantation system, the poor whites who found themselves increasingly disgraced and who at the same time found that their land was in demand, the slave-holder who wished a large tract of virgin soil. It is very important to note that these forces were merely beginning to operate in the time from 1814 to 1818, and that they did not reach their maximum of influence until after 1830, yet as the population of Illinois increased less than twenty-eight thousand from 1810 to 1818, it is altogether probable that a considerable proportion were influenced by the causes suggested. It is also true that some pioneers moved merely from habit, without any well-defined cause.