Were we to go beneath the soil and collect all the mineral and lapidarious wealth of the free States, we should find it so much greater than the corresponding wealth of the slave States, that no ordinary combination of figures would suffice to express the difference. To say nothing of the gold and quicksilver of California, the iron and coal of Pennsylvania, the copper of Michigan, the lead of Illinois, or the salt of New-York, _the marble and freestone quarries of New England are, incredible as it may seem to those unacquainted with the facts, far more important sources of revenue than all the subterranean deposits in the slave States_. From the most reliable statistics within our reach, we are led to the inference that the total value of all the precious metals, rocks, minerals, and medicinal waters, annually extracted from the bowels of the free States, is not less than eighty-five million of dollars; the whole value of the same substances annually brought up from beneath the surface of the slave States does not exceed twelve millions. In this respect to what is our poverty ascribable? To the same cause that has impoverished and dishonored us in all other respects--the thriftless and degrading institution of slavery. Nature has been kind to us in all things. The strata and substrata of the South are profusely enriched with gold and silver, and precious stones, and from the natural orifices and aqueducts in Virginia and North Carolina, flow the purest healing waters in the world. But of what avail is all this latent wealth? Of what avail will it ever be, so long as slavery is permitted to play the dog in the manger? To these queries there can be but one reply. Slavery must be suppressed; the South, so great and so glorious by nature, must be reclaimed from her infamy and degradation; our cities, fields and forests, must be kept intact from the unsparing monster; the various and ample resources of our vast domain, subterraneous as well as superficial, must be developed, and made to contribute to our pleasures and to the necessities of the world. A very significant chapter, and one particularly pertinent to many of the preceding pages, might be written on the Decline of Agriculture in the Slave States; but as the press of other subjects admonishes us to be concise upon this point, we shall present only a few of the more striking instances. In the first place, let us compare the crops of wheat and rye in Kentucky, in 1850, with the corresponding crops in the same State in 1840--after which, we will apply a similar rule of comparison to two or three other slaveholding states. KENTUCKY. Wheat, bus. Rye, bus. Crop of 1840 4,803,152 1,321,373 " " 1850 2,142,822 415,073 --------- -------- Decrease 2,660,330 bus. Decrease 906,300 bus. TENNESSEE.