This work is the first instalment of the greatest popular enterprise in the world, the initial fulfilment of a promise which America has made to herself and all the other nations,--one which shall be completely fulfilled only when an iron highway stretches across her entire breadth, from the Atlantic to the Pacific Ocean. As a people we have grudged neither time nor money to the accomplishment of this end. We have dared the fiery desert and the frozen mountaintop, the demons of thirst, starvation, and savage warfare. Our foremost scientific men, for the sake of the great national enterprise, have taken their lives in their hands, going out to meet peril and privation with the cheerful constancy of apostles and martyrs. The record of expeditions bearing either directly or indirectly on the subject of the Pacific Railroad is one to which every American citizen must point with a pride none the less hearty for the fact that its route has not yet been absolutely decided. The one curse mingled with a young republic's many blessings is the intrusion of political influences into the dispassionate field of national enterprise. We might have determined the line of our Pacific Road before the breaking out of the Rebellion, and by this time its first or Great-Plains section should have been in running order, but for the partisan jealousies which prevailed in high places between the advocates of the different routes. Slavery, that _enfant gate_ of our old-school and now happily obsolete statecraft, insisted on the expensive toy of a southern and unpractical line, until our representatives, harassed by the problem how to gratify her without incurring the contempt of the financial world, gave over to the drift of events the settlement of their country's chief commercial question. We are now in a position to decide coolly; no entangling alliances with a dead-weight social system bias our plain judgment of practical pros and cons; but the opportunity for decision arrives a little too late and a little too early for action. Congress, the legitimate custodian of the Pacific Railroad, may be said to have passed the last four years in climbing to the level of the country's vital exigency. Till Congress reaches that and understands it fully, there is no surplus energy to be thrown away on the else paramount matters of a peaceful age. But it must not be forgotten that the Pacific Railroad stands next to the maintenance of National Unity on the docket of causes for adjudication by our representative tribunal. The people have filed it away till the grand appeal is settled; but they have not forgotten it.