for the basis will be abundant; real estate will increase in value, agricultural productions and agricultural labour will advance at once 10, 15, 20, 30, or 40 per cent., even to as great an extent, perhaps, as was witnessed when the demand came from Ireland for the food of this country to feed the starving Irish.  New York and her sister cities will be the centre of all those revolutionary movements which are certain to spring from the gold productions of California, on the commerce of the whole civilized world.  Ship-building will increase in value, steam-boats will be wanted, the railroads projected across the Isthmus in various places, in Mexico and Central America will be pushed to completion, and we should not be surprised to see an active attempt made, under the auspices of the Federal Government, to construct a railroad across the continent, through the South Pass, from St. Louis, or some other point on the Mississippi, to San Francisco.  The discovery of these great gold mines will no doubt form the agent of the greatest revolution in the commercial centres of the world and on the civilisation of the human race that has ever taken place since the first dawn of history.  New York will henceforth, from its position to the Pacific and Atlantic Oceans, probably in less than a quarter of a century, present a population greater than that of Paris, and display evidences of wealth, grandeur, magnificence, and industry, in an equal if not greater degree than what we see in London at this day.  We expect that, in the next twenty-five years, we shall make as rapid a march in this metropolis, and in the neighbouring cities, as any city has done during the last twenty-five centuries.  There is no necessity for all going to California.  Those who remain, and will raise produce, manufacture goods, build ships, construct steam-engines, and advance the Fine Arts, will enjoy the benefits of those discoveries to as great an extent as those who go to the Sacramento to dig for gold.  All the results of the labours of those diggers must come to this metropolis, swell its magnificence, and increase the intensity of its action in commercial affairs.  Even in a political point of view the discovery of these wonderful gold mines in California, under the Government of the United States, will have a wonderful and astounding effect.  We should not be surprised to see, in a short time, all the old provinces of Mexico, as far as the Isthmus of Darien, knocking for admission into this union; while, on the other side, the British provinces of Canada, and even the Spanish island of Cuba, may be begging and praying to be let in at the same time, and be permitted to enjoy some of the vast advantages, and participate a little in the energy, which this vast confederacy will exhibit to the astonished world.”