Classes. 1790 to 1800 to 1810 to 1820 to 1830 to 1840 to 1800 1810 1820 1830 1840 1850 Whites 35.7 36.2 34.19 33.95 34.7 38.28 Free 88.2 72.2 25.25 36.85 20.9 10.9 col. Slaves 27.9 33.4 29.1 30.61 23.8 28.58 Total 32.2 37.6 28.58 31.44 23.4 26.22 col. Total 35.01 36.45 33.12 33.48 32.6 36.25 pop. The census had been taken previously to 1830 on the 1st of August; the enumeration began that year on the 1st of June, two months earlier, so that the interval between the fourth and fifth censuses was two months less than ten years, which time allowed for would bring the total increase up to the rate of 34.36 per cent. The table given below shows the increase for the sixty years, 1790 to 1850, without reference to intervening periods: Number. 1790. 1850. Absolute Incr. per Increase. cent. Whites 3,172,364 19,631,799 16,459,335 527.97 Free col. 59,466 428,637 369,171 617.44 Slaves 697,897 3,198,324 2,500,427 350.13 Total free 757,363 3,626,961 2,869,598 377.00 col. and slaves Total pop. 3,929,827 23,258,760 19,328,883 491.52 Sixty years since, the proportion between the whites and blacks, bond and free, was 4.2 to one. In 1850, it was 5.26 to 1, and the ratio in favor of the former race is increasing. Had the blacks increased as fast as the whites during these sixty years, their number, on the first of June, would have been 4,657,239; so that, in comparison with the whites, they have lost, in this period, 1,035,340. This disparity is much more than accounted for by European emigration to the United States. Dr. Chickering, in an essay upon emigration, published at Boston in 1848—distinguished for great elaborateness of research—estimates the gain of the white population, from this source, at 3,922,152. No reliable record was kept of the number of immigrants into the United States until 1820, when, by the law of March, 1819, the collectors were required to make quarterly returns of foreign passengers arriving in their districts. For the first ten years, the returns under the law afford materials for only an approximation to a true state of the facts involved in this inquiry.