the present.  The avenging Providence, which the slaveholder cannot find in the New Testament, or in the teachings of conscience, he is at last compelled to find in political economy; and however indifferent to the Gospel according to Saint John, he must give heed to the gospel according to Adam Smith and Malthus.  He discovers, no doubt to his surprise, and somewhat to his indignation, that there is an intimate relation between industrial success and justice; and however much, as a practical man, he may despise the abstract principles which declare Slavery a nonsensical enormity, he cannot fail to read its nature, when it slowly, but legibly, writes itself out in curses on the land.  He finds how true is the old proverb, that, “if God moves with leaden feet, He strikes with iron hands.”  The law of Slavery is, that, to be lucrative, it must have a scanty population diffused over large areas.  To limit it is therefore to doom it to come to an end by the laws of population.  To limit it is to force the planters, in the end, to free their slaves, from an inability to support them, and to force the slaves into more energy and intelligence in labor, in order that they may subsist as freemen.  People prattle about the necessity of compulsory labor; but the true compulsory labor, the labor which has produced the miracles of modern industry, is the labor to which a man is compelled by the necessity of saving himself, and those who are dearer to him than self, from ignominy and want.  It was by this policy of territorial limitation, that Henry Clay, before the annexation of Texas, declared that Slavery must eventually expire.  The way was gradual, it was prudent, it was safe, it was distant, it was sure, it was according to the nature of things.  It would have been accepted, had there been any general truth in the assertion that the slaveholders were honestly desirous of reconverting, at any time, and on any practicable plan, their chattels into men.  But true to the malignant principles of their system, they accepted the law of its existence, but determined to evade the law of its extinction.  As Slavery required large areas and scanty population, large areas and scanty population it should at all times have.  New markets should be opened for the surplus slave-population; to open new markets was to acquire new territory; and to acquire new territory was to gain additional political strength.  The expansive tendencies of freedom would thus be checked by the tendencies no less expansive of bondage.  To acquire Texas was not merely to acquire an additional Slave State, but it was to keep up a demand for slaves which would prevent Virginia, North Carolina, Maryland, and Kentucky from becoming Free States.  As soon as old soils were worn out, new soils were to be ready to receive the curse; and where slave-labor ceased to be profitable, slave-breeding was to take its place.