When the iron trains are at the front, the laying will for a short time proceed at the rate of nine yards in every fifteen seconds; but three or four hundred tons of rails have to be brought up every day upon the single track, and it is in this that the time is lost. The advance carriages of the construction train are well supplied with rifles hung from the roofs; but even when the Indians forget their amaze, and attack the “city upon wheels,” or tear up the track, they are incapable of destroying the line so fast as the machinery can lay it down. “Soon,” as a Denver paper said, during my stay in the Mountain City, “the iron horse will sniff the Alpine breeze upon the summit of the Black Hills 9000 feet above the sea;” and upon the plateau, where deer are scarce and buffalo unknown, the Indians have all but disappeared. The worst Indian country is already crossed, and the red men have sullenly followed the buffalo to the south, and occupy the country between Kansas State and Denver, contenting themselves with preventing the construction of the Santa Fé and Denver routes to California. Both for the end in view, and the energy with which it is pursued, the Pacific Railroad will stand first among the achievements of our times. If the end to be kept in view in the construction of the first Pacific Railroad line were merely the traffic from China and Japan to Europe, or the shortest route from San Francisco to Hampton Roads, the Kansas route through St. Louis, Denver, and the Berthoud Pass would be, perhaps, the best and shortest of those within the United States; but the Saskatchewan line through British territory, with Halifax and Puget Sound for ports, would be still more advantageous. As it is, the true question seems to be, not the trade between the Pacific and Great Britain, but between Asia and America, for Pennsylvania and Ohio must be the manufacturing countries of the next fifty years. Whatever our theory, the fact is plain enough: in 1870 we shall reach San Francisco from London in less time than by the severest traveling I can reach it from Denver in 1866.