Rev. Stuart Robinson, speaking before the Kentucky Colonization Society in 1849, gave another viewpoint of the economic value of the slave. "The increase of slaves in Kentucky," said he, "has hardly reached three thousand annually for eighteen years past. The increase since 1840 has been 27,653--the increase for the year just closed 2,921. In twenty-six counties, embracing one fourth of the slave population--some of them the largest slave-holding counties--there has been an actual decrease in the last year of 881 slaves. In twelve other counties the increase has been only twenty-three. There are ten counties in the State, which contain one third of all the slave population of Kentucky; in these ten counties, the increase of slaves for five years past has been 2,728--an increase of less than one per cent per annum. Nor is this slow increase of slavery to be attributed to any stagnation or decline of public prosperity, for in the meantime the state has been growing in population and wealth as heretofore. During these five years the taxable property of the Commonwealth has increased in value more than seventy-six millions. Now this decrease of slaves while the other property of the commonwealth is increasing must arise from one of three causes--and in either case the inference is the same as to the fate of slavery in Kentucky. (1) Is it because the climate is unhealthy to the African? If so then African labor cannot continue. (2) Is it owing to emigration? Then something is wrong in the system of labor, that causes the emigration of our people--for no finer soil--no more desirable residence can be found in the world. (3) Or is it owing to the domestic slave trade? Then for some reason slave labor is less profitable here than elsewhere, and must soon be given up."[283] These figures quoted by the speaker on the slave population for year by year are available in the auditor's tax books for the years 1840 to 1859:[284] 1840 164,817 1841 168,853 1842 171,035 1843 176,107 1844 178,837 1845 182,742 1846 185,582 1847 189,549 1848 192,470 1849 195,110 1850 196,847 1851 196,336 1852 200,867 1853 200,015 1854 200,181 1855 202,790 1856 201,160 1857 201,590 1858 207,559 1859 208,625 The very small growth shown here would barely account for the natural increase among the slaves by virtue of the high birth rate. The mortality rates were about the same for slaves as for whites. The relative decline was undoubtedly due to the rising prices for slaves which were sent to the South and the consequent decreasing value of a slave's labor to the Kentuckian. He knew beyond a doubt that the time would eventually come when he would have to part with his slave and that portion of the holders who were not averse to selling their chattels did so during this period.