THE CAHUILLA BASIN AND DESERT OF THE COLORADO. 



By William Pmprs Blake. 1 



EXPLORATION. 



The year 1853 was notable in the history of explorations of United States territory 

 west of the Mississippi River. In that year, under the administration of President Pierce, 

 with Jefferson Davis as Secretary of War, four fully equipped expeditions, authorized by 

 Congress, were sent out to explore the almost unknown country lying between the Mississippi 

 River and the Pacific Ocean, to look for and determine a practicable route for a railway. 



Our knowledge of the country at that date may be summarized as follows: Aside 

 from the early exploration in the northwest, Fremont, in his daring overland explorations, 

 had made us acquainted with the obstacles and perils of a route across the Sierra Nevada; 

 Stansbury had told us of the great Salt Lake; Sitgreaves had crossed Arizona south of the 

 Grand Canyon, entering what is now California near the mouth of Bill Williams Fork. 

 Emory had made a rapid military reconnaissance of the route from Fort Leavenworth, 

 Missouri, to San Diego, in California. 



To one of the expeditions of 1S53 was assigned the duty of following the Sierra Nevada 

 of California southward, to seek for any suitable pass through which a railway might be 

 built. This survey was placed in charge of Lieut. R. S. Williamson, of the United States 

 Topographical Engineers, with Lieut. J. G. Parke second in command, and the writer 

 as geologist. Walker's Pass, much vaunted at the time as the best and only practicable 

 pass in the Sierra Nevada, was the first objective point. It was most favored by Senator 

 Gwin of California, who had personally taken the field and journeyed as far south as the 

 Tejon, from whose summit he could see a favorable route across the Great Basin eastward. 

 The Williamson expedition made surveys of Walker's Pass, the Taheechapah (the orthog- 

 raphy of which has been corrupted to Tehachipi), Tejon, Canada de Las Uvas, the passes 

 north of Los Angeles, and the Cajon from the Mojave to San Bernardino, without finding 

 any pass that offered an especially favorable and easy route or inviting grades. 



SAN GORGONIO PASS. 



Imagine, then, the enthusiasm with which the unknown great break in the mountain 

 range between San Bernardino and San Jacinto was approached by the members of the 

 party as we made our way eastward from the region, then practically unoccupied but now 

 including the towns of Colton and Redlands, and found an easy grade and open country 

 for our train of wagons to the summit, only 2,5S0 feet above the sea. Here, at last, was 

 discovered the greatest break through the western Cordillera, leading from the slopes 

 of Los Angeles and the Pacific into the interior wilderness. It had no place upon the maps 

 and had not been traversed by surveying parties or wagons. From the summit, we could 

 look eastward and southward into a deep and apparently interminable valley stretching 

 off in the direction of the Gulf of California. This pass was evidently the true gateway 

 from the interior to the Pacific Ocean. (Plate 1 a.) 



1 This paper was prepared by Professor Blake two years prior to his death in 1910 with a view to its publication 

 in conjunction with a series of other essays upon the control of the Colorado River by the American Society ot Civil 

 Engineers. The manuscript, however, was found to be more suitable to the present volume aud was secured tor 

 publication here through the kind offices of Mr. H. T. Cory. But few alterations have been made, and these consist 

 chiefly in omissions of sections bearing upon the vegetation and other topics which are more fully treated elsewhere. 

 The paper possesses a peculiar interest, since it is based upon observations begun by the author with his discovery 

 of the basin-like character of the region in 1S53 and extended to his last visit in May 1906. 



