Southern gentlemen, when they threaten disunion, cannot surely be so much at fault as to forget that slavery exists here as it never existed before in the world. In Greece there were slaves;--in some cases, highly intelligent and accomplished slaves. They could have escaped if they would; but where should they escape to? All coterminous nations,--the whole circle round,--were barbarians. These slaves, therefore, had no place to flee to, where better institutions and juster laws prevailed. So it was with Rome. Whither could her slaves fly but to barbarous Spain, or more barbarous Gaul, or to some nation whose language they did not understand. Ignorance of language is a more insuperable barrier than mountains or oceans. It is just the reverse here. The English language is spoken on all sides; and our slave land is encircled by free land or free ocean,--Jamaica, the Bermudas, and two thousand miles of northern frontier. And I have lately seen an estimate from a credible source, that if an inter-oceanic canal should be opened across the Isthmus of Darien, twelve hundred ships would annually pass through it; and, as they sail to and fro, they will skirt the whole of your gulf coast, and the whole of your Atlantic coast, a great part of the voyage being within sight, or within a day’s sail, of your shores. Now, the ignorant slave knows but little of geography, but he would know of these avenues to freedom, and nothing but death could extinguish such knowledge and the hopes it would inspire. I say, sir, under such circumstances, slavery would melt away upon your borders like an iceberg in the tropics. The particles, that is, the individuals of the exposed surface, would disappear; and you might as well attempt to stop solar evaporation by statutory laws, as to prevent their escape. Perhaps a dissolution of the Union is the means foreordained by God for the extinction of slavery; and did I not foresee its doom before any very long period shall have elapsed, without the unspeakable horrors of a civil and a servile war, I cannot say to what conclusion the above considerations would lead my own mind.