The cultivation of rice[80] and sugar, especially sugar, used up slaves rapidly. As a consequence slaves were in demand in the rice and sugar sections, not only because of the expansion of these industries, but to take the place of those that died. In 1829 the statement was made in a report of the Agricultural Society of Baton Rouge, Louisiana, that the annual loss of life on well conducted sugar plantations was two and one-half per cent. more than the annual increase. In 1830, the Hon. J.L. Johnson in a letter to the Secretary of the Treasury gave evidence of a thorough study of the subject and arrived at the same conclusion.[81] We come now to consider the one thing, the prime factor, which brought about the wonderful agricultural prosperity of the Southwest--_cotton_. Sugar and rice could only be grown in certain limited sections. Rice principally in South Carolina and sugar in Louisiana; but the cotton field came to cover the larger part of nine great States. Until toward the end of the eighteenth century the production of cotton in this country was very small. In 1793, however, Eli Whitney invented his machine for separating the seed from the cotton. This soon revolutionized the industry. While the cotton crop of the United States in 1793 was only 5,000,000 pounds, by 1808 it had increased to 80,000,000, and remained about the same or rather declined during the war of 1812, but the very year peace was established its production went up to 100,000,000 pounds, and the year following (1816) to 125,000,000. By 1834 it had grown to 460,000,000.[82] During the whole of this period, with slight fluctuations, cotton continued high, but after 1835 it began to decline and reached low-water mark at the average price of 5-3/4 cents per pound in 1845, which was scarcely the cost of production.[83] However, the crop of 1839 according to the census reports was 790,479,275 pounds, nearly double the crop of the five years previous. During the next decade though the price went up after 1845[84] the crop increased less than 200,000,000 pounds being only 987,637,200 in 1849, but during the following ten years it more than doubled, being 2,397,238,140 pounds in 1859.[85] Of this enormous crop the four States of Mississippi, Alabama, Louisiana and Georgia produced more than two-thirds, while Virginia contributed about 1,400.[86] But Virginia and North Carolina in 1801 had produced more than two-fifths of the cotton raised in the country. In 1826 when, according to the official reports they reached their greatest production, Virginia grew 25,000,000 pounds and North Carolina 18,000,000, or nearly five times as much as in 1801, yet this proportion had fallen to about one-seventh. Eight years afterward Virginia's crop had fallen to 10,000,000 pounds and North Carolina's to 9,500,000,[87] and their production continued to decline.[88] Hammond says that "the higher cost of raising cotton in the more northern