Already, in 1858, he had written and published, at his own expense, a pamphlet of twenty-three pages, entitled "The Great Commercial Prize," Boston, A. Williams & Co. It cost him fifty dollars, then a large sum for him, from which the advantage accrued to the nation at large. It was addressed to every American who values the prosperity of his country. It was "An inquiry into the present and prospective commercial position of the United States, and a plea for the immediate construction of a railroad from Missouri River to Puget Sound." It opens with a review of the great events in the world which have had a direct and all-important bearing upon the United States. Hitherto, since the modern mastery of the ocean through the mariner's compass and the science of navigation, the Atlantic had been the domain of sea power. The Pacific was in future to be the scene of greater opportunities and grander commercial developments. With China and Japan entering the brotherhood of nations, and Russia extending its power towards the Pacific, "five hundred millions of human beings were henceforth to be reached by the hand of civilization." The countries and continents bordering the greatest of oceans were animated with new ideas of progress. On our own western shores, California, Oregon, and Washington were awaiting the touch of industry to yield their riches. As a reader of the signs of the times, Carleton pointed out the great changes which were to take place in the thoroughfares of trade and travel. Instead of civilization depending for its communication with India, China, and Japan, by passages around the southern capes of the two continents, the paths of water and land traffic were to be directly from China, Russia, and Japan to northern America. Noticing that England had made herself the world's banking-house, he saw that the time had come when the United States (which he believed to be potentially, at least, a larger and a nobler England) must stretch out her left hand, as well as her right, for the grasping of the world's prizes. He pointed out the wonderful openings along the shore, providing harbors at the mouths of the two great river systems on the Pacific Coast, those of the Sacramento and the Columbia.