slaves are consumers to the amount of dls 75,000,000 a year. In 1845 the annual earnings of the State of Massachusetts were dls 114,492,636. This does not include the improvements made on the soil, nor bridges, nor railroads, highways, houses, shops, stores, and factories that were built—these things form a permanent investment for future years. It cannot reasonably be supposed that, in addition, so large a sum as fourteen per cent, of the annual earnings is saved and laid by. But on that supposition, the 737,699 inhabitants of Massachusetts are consumers to the amount of dls 100,000,000 a year; that is, dls 25,000,000 more than four times that number of slaves would consume. The amount of additional energy, comfort, and happiness is but poorly indicated even by these figures.
In the present age, slavery can compete successfully with free labour only under rare circumstances. The population must be sparse; perhaps not exceeding fifty persons to the square mile. But in the nice labour and minute division of employment, in the economy and the improved methods of cultivation, consequent on a dense population, slavery ceases to be profitable; the slave will not pay for rearing. It must be on a soil extraordinarily fertile, which the barbarous tillage of the slave cannot exhaust. Some of the rich lands of Georgia, Alabama, Louisiana, and Mississippi are of this character. Then it must have the monopoly of some favourite staple, which cannot be produced elsewhere. A combination of those three conditions may render slavery profitable even at this day, yet by no means so profitable as the work of the freeman. Mr Rutledge was not far from right in 1787, when he contended that, in direct taxation, a slave should pay but one third as much as a freeman, his labour being only of one third the value of a freeman's.
In the Northern States, the freeman comes directly in contact with the material things which he wishes to convert to his purpose. To shorten his labour he makes his head save his hands. He invents machines. The productive capacity of the free States is extended by their use of wind, water, and steam for the purposes of human labour. That is a solid gain to mankind. Wind mills, water-mills, steam-engines, are the servants of the North; homebred slaves born in their house, the increase of fertile heads.
