Colonel Roosevelt's own books, notably "Hunting Trips of a Ranchman," "Ranch Life and the Hunting Trail," "The Wilderness Hunter," and the "Autobiography," have furnished me an important part of my material, giving me minute details of his hunting experiences which I could have secured nowhere else; and I am indebted to the publishers, Messrs. G. P. Putnam's Sons, Messrs. Charles Scribner's Sons, and the Century Company, for permission to use them. I am indebted to the following publishers, likewise, for permission to reprint certain verses as chapter headings: Messrs. Houghton Mifflin Company ("Riders of the Stars," by Henry Herbert Knibbs, and "Songs of Men," edited by Robert Frothingham); the Macmillan Company ("Cowboy Songs," edited by Professor John A. Lomax); and Mr. Richard G. Badger ("Sun and Saddle Leather," by Badger Clark). I am especially indebted to Mr. Roosevelt's sisters, Mrs. W. S. Cowles and Mrs. Douglas Robinson, and to the Honorable Henry Cabot Lodge for the opportunity to examine the unpublished letters of Colonel Roosevelt in their possession and to reprint excerpts from them. Through the courtesy of Mr. Clarence L. Hay I have been able to print a part of an extraordinary letter written by President Roosevelt to Secretary Hay in 1903; through the courtesy of Messrs. Harper and Brothers I have been permitted to make use of material in "Bill Sewall's story of T. R.," by William W. Sewall, and in "The Boys' Life of Theodore Roosevelt." Partly from books and letters, partly from documents and old newspapers, I have gathered bit by bit the story of Roosevelt's life as a ranchman; but my main sources of material have been the men and women (scattered now literally from Maine to the State of Washington) who were Roosevelt's companions and friends. It is difficult to express adequately my gratitude to them for their unfailing helpfulness; their willingness to let themselves be quizzed, hour after hour, and to answer, in some cases, a very drumfire of importunate letters; above all for their resistance, to what must at times have been an almost overpowering temptation, to "string the tenderfoot." They took my inquisition with grave seriousness and gave me what they had without reserve and without elaboration.