For the titles of works of reference, of the narratives of trappers, etc., I refer to the works of H. H. Bancroft; to Warren’s _Memoirs_, vol. i. Pacific Railroad reports; and to the first volume of Lieut. Geo. M. Wheeler’s report on Explorations West of the 100th Meridian. The trappers and prospectors who had some experience on the Green and the Colorado have left either no records or very incomplete ones. It seems tolerably certain, however, that no experience of importance has escaped notice. So far as attempts at descent are concerned, they invariably met with speedy disaster and were given up. In writing the Spanish and other foreign proper names I have in no case translated, because such translations result in needless confusion. To translate “Rio del Tizon” as Firebrand River is making another name of it. Few would recognise the Colorado River under the title of Red River, as used, for example, in Pattie’s narrative. While Colorado means red, it is quite another matter as a _name_. Nor do I approve of hyphenating native words, as is so frequently done. It is no easier to understand Mis-sis-sip-pi than Mississippi. My thanks are due to Mr. Thomas Moran, the distinguished painter, for the admirable sketch from nature he has so kindly permitted a reproduction of for a frontispiece. Mr. Moran has been identified as a painter of the Grand Canyon ever since 1873, when he went there with one of Powell’s parties and made sketches from the end of the Kaibab Plateau which afterwards resulted in the splendid picture of the Grand Canyon now owned by the Government. I am indebted to Prof. A. H. Thompson for the use of his river diary as a check upon my own, and also for many photographs now difficult to obtain; and to Dr. G. K. Gilbert, Mr. E. E. Howell, Dr. T. Mitchell Prudden, and Mr. Delancy Gill for the use of special photographs. Other debts in this line I acknowledge in each instance and hence will not repeat here. I had hoped to have an opportunity of again reading over the diary which “Jack” Sumner kept on the first Powell expedition, and which I have not seen since the time of the second expedition, but the serious illness of Major Powell prevented my requesting the use of it. F. S. Dellenbaugh. New York, October, 1902. NOTE.—Since the last edition of this work was published, the inquiries of Mr. Robert Brewster Stanton have brought to light among some forgotten papers of Major Powell’s at the Bureau of Ethnology in Washington the diary of Jack Sumner and also that of Major Powell himself. Both begin at the mouth of the Uinta River. Major Powell, because of his one-armed condition, had the only life-preserver. The preserver was rubber of the inflating type and is in the Smithsonian Institution, presented by Mr. Stanton who obtained it from one of the survivors in 1907. NOTE ON THE AUTHOR’S ITINERARY IN THE BASIN OF THE COLORADO RIVER AND ADJACENT TERRITORY (Except where otherwise stated journeys were on horseback.)