The North, however, did not take up arms to destroy slavery, but the Right of Secession, since that was the irritating _point d'honneur_, and, what was more, the real first cause of injury which at first presented itself. Mr. Lincoln had cause to know that in the beginning, even in the South itself, secession was only the work of a turbulent minority. 'To have yielded would have been to have written himself down before the world as incompetent--nay, as a traitor to the cause which he had just sworn to defend.' In short, we were misunderstood--painfully so--and it is not a matter of indifference to learn that at last there is a reaction of intelligence in our favor, and that light is breaking through the bewildering mists which once veiled the truth. In discussing 'the economic basis of slavery,' Professor Cairnes deals out truths with a prompt vigor which is truly admirable. From Stirling, Olmsted, Sewell, and others, he disposes of the old falsehood that only the negro can endure the Southern climate--a fact but recently _generally_ made known at the North--that isothermal lines do not follow the parallels of latitude--and that it is a gross error to believe the black incapable of improvement as a freeman. He admits that slave labor has its advantages, in being absolutely controllable, and in returning the whole fruit of its labor to the owner. It may, therefore, be combined on an extensive scale, and its cost is trifling. But, on the other hand, slave labor is given reluctantly, and is consequently a losing means, unless much of it can be concentrated under the eye of one overseer. It is unskillful, because the slave cannot be educated; and, therefore, having once learned one thing, he must be kept at that for life. The result of this is that, as the slave, unlike the free farm-laborer, cannot (with rare exceptions) be profitably employed at aught save agriculture, and indeed only at one branch of that, he soon exhausts the soil. If all the blacks in the South were capable of laboring at rotation of crops, they would soon be free. Slavery has always of itself died out in the wheat and corn regions--because, in raising cereals, labor is more widely dispersed than in cotton or tobacco planting, and the workers are more difficult to oversee. Hence the constant immigration from the wornout to the new plantation, and the cry for new land; and hence the admission, by the most intelligent men of the South, that to prevent the extension of slavery would be to destroy it. Free labor flourishes even on barren soils--ingenuity is stimulated and science developed. But slave labor requires abundance of fertile soil and a branch of culture demanding combination and organization of large masses of labor and its _concentration_.