"When, however, my attention was directed to the study of the various researches which have been made in the regions now known as Kanzas and Nebraska, I knew that I had a wide range before me. I have followed up, as carefully as I could, the memoirs of the early French travelers who first opened to the civilized world the valley of the Missouri. Of more use, in the view in which that valley is now regarded, are the more recent travels of our own countrymen, a body of official reports which deserve very high praise for the skill and gallantry displayed in exploration, and the care with which their history has been written. I have made such use as I could of the travels of Lewis and Clark, Capt. Pike, Col. Long, Mr. Breckenridge, Maj. Bonneville, Col. Fremont, Col. Emory, Lieut. Abert, Mr. Parkman, Maj. Cross, Capt. Stansbury, Capt. Gunnison, Gov. Stevens, Lieut. Williamson, and others.
"Since the formation of the Emigrant Aid Companies, I have been deeply interested in their success. The trustees of the Boston company offered me, very kindly, any assistance in their power; but they are in no sense responsible for my opinions, as expressed here. I should never have undertaken this work, however, but from a wish to assist in the great enterprise of settling Kanzas at once,-an enterprise which appears to me to open a nobler field for effort than any public undertaking which has called upon our energies for many years. To contribute as I could to the immediate settlement of Kanzas, I have given such hints to emigrants, and special information for their wants, as my materials afforded me."