It is apparent, then, that, as regards easy access to the West, the natural advantages of Virginia surpass New York, and with greater facilities for artificial works. How many decades would be required, after emancipation, to bring the superior natural advantages of Virginia into practical operation, is not the question; nor do I believe that the city of New York will ever cease to be the centre of our own trade, and ultimately of the commerce of the world. But although Virginia, in adhering to slavery, has lost her supremacy in the Union, it is quite certain that, as a Free State, she would commence a new career of wonderful prosperity, that capital and population from the North and from Europe would flow there with a mighty current, her lands be doubled in value, and her town and city property far more than quadrupled. MINES.--Virginia has vast mines of coal, the great element of modern progress. New York has none. It is coal that has made Great Britain a mighty empire, giving her power, by land and sea, equal to the manual force of all mankind. It is stated by the Commissioner of the General Land Office, in his report before referred to, of November, 1860, 'that an acre of coal, three feet thick, is equal to the product of 1,940 acres of forest trees; and each acre of a coal seam four feet in thickness, and yielding one yard of pure coal, is equivalent to 5,000 tons, and possesses, therefore, a reserve of mechanical strength in its fuel, equal to the life labor of more than 1,600 men.' This statement of the Commissioner is made on the highest authority, and proves the vast natural advantages of Virginia over New York. Virginia, also, has far more abundant mines of iron, more widely diffused over the State, reaching from tide water to the Ohio. She has also these iron mines in juxtaposition with coal and all the fluxes. Virginia, also, has valuable mines of gold, lead, and copper. New York has no gold or copper mines, and produced in 1860 but $800 worth of lead. (Table 14.) HYDRAULIC POWER.--Omitting Niagara, which thus far scorns the control of man, the hydraulic power of Virginia very far exceeds that of New York. It is to be found on the Potomac and its tributaries, and upon nearly every stream that flows into the Chesapeake or Ohio. The superior mildness of the climate of Virginia makes this power available there for a much greater portion of the year. The great falls of the Potomac, where Washington constructed the largest locks of the continent, has a water power unsurpassed, and is but twelve miles from tide water, at Washington. This point is a most healthy and beautiful location, surrounded by lands whose natural fertility was very great, and, in the absence of slavery, must have been a vast manufacturing city. This water power could move more spindles than are now worked on all this continent.