The slave State which has increased most rapidly to the square mile of all of them from 1790 to 1860, has had a smaller augmentation per square mile than that free State which has increased most slowly per square mile during the same time of all the free States, and the result is the same as to wealth and education also. Under the best circumstances for the slave States, and the worst for the free States, this result proves the uniformity of the rule (like the great law of gravitation), knowing no exception to the effect of slavery, in depressing the progress of States in population, wealth, and education. Would we then in all these advance more rapidly, we must remove slavery and negroism, the retarding cause. I know it is asked, how shall we then cultivate the cotton lands of the South without slaves? This does not apply to the border States; but before closing these letters, I will prove conclusively, by the census and other statistics, what, from long residence in the South, and from having traversed every Southern State, I know to be true, that cotton is now raised there most extensively and profitably by non-slaveholders, and upon farms using exclusively white labor. Indeed the cotton raised on small farms in the South where there are no slaves and exclusively by free white labor, commands a price from five to ten per cent. greater than the slave grown cotton. In Texas, especially, it is a great truth, that skilled, educated, persevering, and energetic free labor, engaged voluntarily for wages or its own use, would, in time, when aided by improved culture and machinery, produce much larger crops and better cotton than now raised by the forced and ignorant labor of slaves, and at a much cheaper rate, at a far greater profit, than any crop now produced in the North, and in a more salubrious climate. In western Texas, counties on the same parallel with New Orleans, and a little north and south, cultivated mainly by Germans without slaves, produced large quantities of the best cotton, and the supply with augmented labor might be increased almost indefinitely. Having thrice visited Texas, and traversed nearly the whole State, north, south, east, and west, I speak from personal knowledge. In one county, I observed first rate wheat, cotton, and sugar cane growing in adjacent fields, and the soil and climate well adapted for all three crops. In Texas, the product of wheat has increased from 41.79 bushels in 1850, to 1,464,273 bushels in 1860, and the number of bales of cotton from 58,072 in 1850, to 405,100 bales in 1860, far exceeding the rate of increase in any other State. (See table of Census, No. 36, pp. 200, 210.) Having very nearly six times the area of New York, Texas, when cultivated by free labor, can produce cotton enough to clothe the people of the world, and supply all Europe with wheat also. The rapid colonization of Texas by freemen ought to add to our wealth, in this decade, a sum equal to the present debt of the United States, and terminate in our favor the effort to supplant us in the supply of cotton for the world.
The isothermals of the great Humboldt (differing so widely from parallels), which trace the lines of temperature on the earth's surface, prove, as to heat, the climate of the South (running a line from Charleston to Vicksburg) to be substantially the same as that of Greece and Italy—each, in its turn, the mistress of the world. I know, when, the term isothermal was used in my inaugural as Governor of Kansas, it was represented by some of our present rebel leaders, to the masses of the South, as some terrible monster, perhaps the Yankee sea serpent; but I now use the term again in no offence, from its important application to the present case, and knowing that what I now advise would produce incalculable benefits to the whole country, but especially to the South. Indeed, if Texas, with her 274,356 square miles of area, with her salubrious climate, and fertile soil, already worked to a great extent by free labor, were a free State, she would, in time, contain a larger population than any State of the Union. Texas has much more than five times the area of England proper, and, with the same population to the square mile, would contain more than one hundred millions of people. Having, in 1837, offered in the Senate of the United States, and carried, the resolution, recognizing the independence of Texas, first proposing in my letter of the 8th January, 1844, the mode, by compact (alone practicable), by which, on my motion, Texas was admitted into the Union, distinctly advocating, in this letter, the reannexation of Texas, with, a view to secure the ultimate disappearance of slavery and negroism from the whole country, in opposition to the object officially avowed by Mr. Calhoun, to annex Texas for the purpose of perpetuating slavery, I shall, in a future letter, discuss this subject, involving not only our furnishing a certain abundant supply of cheap cotton, but securing the real monopoly of this great product, due to our peculiar soil and climate, and thus ultimately increasing our products and manufactures thousands of millions of dollars, and giving us the control of the commerce of the world.
If Maryland would only initiate this policy, and come now to the rescue of the Union from rebellion and foreign intervention, she would inscribe her name first of all the States on the page of history and in the gratitude of our country and mankind. The position of Maryland upon the Chesapeake, the Potomac, the Susquehanna, and Atlantic, is most commanding. She surrounds the Capitol. It was her own noble donation, and she is its natural guardian and sentinel. Her waters, cutting the Blue mountains and the Alleghany, flow into the Atlantic and Mississippi, thus making her an eastern and a western State. Throughout all her borders, not a citizen would lose anything by the change proposed, but all would be enriched. Take down the barriers of slavery, and a new and unprecedented current of population and capital would flow into the State. Property would rise immensely in value, the price of her lands would soon reach those of Pennsylvania, new towns and cities would spring into life, Cumberland would soon equal the great manufacturing sites of the North, and the railroad to Pittsburg would soon be completed. Baltimore would fulfil her mighty destiny, and the present canal up the Susquehanna, easily enlarged, so as to equal the grand work of New York, would connect her with Lakes Erie and Ontario. That canal already unites the Susquehanna from the Chesapeake with the lakes by the Seneca route (as it should by the Chenango also), and only requires to be enlarged to the extent of the Erie Canal, and the locks also, as wisely proposed in regard to that great work. This would at once develop the great iron and coal mines of the Susquehanna (anthracite and bituminous), supply western and central New York, and the great region of the lakes, and the Chesapeake with these articles, so essential in war and peace. Let the locks of the Erie Canal be enlarged as proposed, and the ship canal from the Illinois river to Chicago constructed; but in justice to Pennsylvania and Maryland, as vastly important for commerce and revenue, and as a war measure for the cheap construction of iron-clad gunboats in the great coal and iron region, and the defence of the lakes, the Chesapeake, the Delaware, the Albemarle, and of the capital of the Union, let this canal be enlarged also.
While this system of gradual emancipation would greatly promote the material interests of Maryland, and of all the border States, the President does not overstate its influence in crushing the rebellion and restoring peace.
Maryland, the border States, and the South would then indeed commence a new career of progress,