"If the movement shall continue five years, our commerce with that territory may reach one hundred millions per annum. This is doubtless a startling sum; but it must be borne in mind that we have to build cities and towns, supply machinery for mining, coal for domestic purposes, and steam navigation, and all the multifarious articles used in providing the comforts and luxuries of life, for half a million of people, who will have transferred themselves to a country which is to produce, comparatively, nothing except minerals and the precious metals, and whose pursuits will enable them to purchase, at any cost, whatever may be necessary for their purposes. "It is difficult to imagine or calculate the effect which will be produced on all the industrial pursuits of the people of the Old States of the Union, by this withdrawal from them of half a million of producers, who, in their new homes and new pursuits, will _give existence_ to a commerce almost equal in value to our foreign trade. Let no one, therefore, suppose he is not interested in the welfare of California. As well may he believe his interests would not be influenced by closing our ports and cutting off intercourse with all the world. "The distance round Cape Horn is so great that bread-stuffs and many other articles of food deteriorate, and many others are so perishable in their nature that they would decay on the passage. This would be the case particularly with all kinds of vegetables and undried fruits. Until some more speedy mode of communication shall be established by which produce can be transferred, the farmers and planters of the old States will not realize the full value of this new market on the Pacific. "Many other important interests will be kept back, especially the consumption of coal. The American steamers, now on that ocean, those on their way there, and others shortly to be sent out, will consume not far from one hundred thousand tons of coal per annum. The scarcity of wood in California will bring coal into general use as fuel, as soon as it can be obtained at reasonable prices. Suppose there may be, three years hence, forty thousand houses, which shall consume five tons each per annum. This, with the steamers, would be a consumption of three hundred thousand tons. If delivered at $20 per ton, it would compete successfully with the coal from Vancouver's Island and New Holland, and amount to $6,000,000. "The construction of a railroad across the Isthmus of Panama would secure the market for those articles against all competition. "Some idea may be formed of the demand for them from the prices paid in San Francisco last autumn. Coal was sold at $60 to $100 per ton; potatoes $16 per bushel; turnips and onions for 25 to 62½ cents each; eggs from $10 to $12 per dozen.