finally joined the party of revolution which overthrew the Mexican rule there. Fremont later testified that his mission was to survey for a railroad to San Francisco Bay, and on that theory alone can his movements be fully explained.
In any event, it was now seen that logically the first step in securing a Pacific railroad was not a land grant but a careful preliminary survey to determine the best line for such a work; and the government's engineering service was amply equipped for making such a survey or surveys. Accordingly, Congress was appealed to in this matter, and on the 3rd of March, 1853, the law was passed which provided for the great Pacific Railroad Surveys. All promising routes were to be investigated — such as the route made familiar through the journey of Lewis and Clark, the routes of Pike, Long, and Fremont, and those reported on by officers connected with the military campaigns in New Mexico and California. The Secretary of War was to direct the surveys and a large measure of discretion was necessarily reserved to him.
The Pacific railway surveys. Secretary Jefferson Davis caused to be examined four routes from the Mississippi to the Pacific. One w^as a northern route, two central and one southern. The northern route ran near the head of the Missouri, one of the two central routes ran near the forty-second parallel (the South Pass route), the other some three or four degrees further south. The southern route was near the thirty-second parallel.
