GEOGRAPHICAL FEATURES OF THE CAHUILLA BASIN. 



15 



His exploration was carried on by boat and extended some distance up the Colorado. 

 Pencilled range marks upon the original map indicate that his chief observational station 

 was upon the south end of Angel Island, and his survey was mainly a marine and coastal one. 



At some time subsequent to the journeys of Fathers Kino and Consag, some other 

 explorer or explorers must have penetrated the region, and the result of this work is to 

 be seen embodied in the remarkable map of John Rocque. 1 (Plate 5.) This map is 

 unique in several respects : The unusual accuracy of its detail over most of North America ; 

 the evidence that the cartographer must have had at his disposal very complete sources 

 of information in regard to the Southwest; but chiefly, as far as the scope of this paper is 

 concerned, from the fact that it clearly shows the combined streams of the Colorado and 

 the Gila flowing into a lake, and having no connection with the Gulf. (Fig. 1.) 



The nomenclature throughout the region shows knowledge of the work of Kino, but 

 this very radical feature in the topography is clearly 

 due to the work of some explorer of whose work we 

 as yet know nothing more. 



A fairly comprehensive search for and exami- 

 nation of the early maps of the Southwest have 

 been made in the hope of finding some conclusive 

 evidence of former fillings of the Salton Basin 

 within historic times, and this map at least seems 

 to indicate that such a diversion of the river water 

 towards the west has been known to travelers at 

 some time between 1706 and 1760. With this clue 

 it is probable that further search may result in giv- 

 ing us positive information upon the subject. A 

 common tradition amongst the Indians of the region 

 points to the fact that such a filling of the Basin 

 has taken place within comparatively recent times, 

 in which the water extended "from mountain to 

 mountain." 



Father Pedro Font traveled in and explored the 

 region in 1776, and doubtless crossed the Colorado 

 Desert at least twice, and also reached the shore of 

 the Gulf on the west side of the river. His map 

 shows a large irregular opening still farther to the 

 west than his own approach to the Gulf, and here 

 again we may have the western opening of the early 

 explorers, or another interpretation of the lake of Rocque. 2 Father Font was the last of 

 the Spanish explorers to add anything to our knowledge of the delta or desert, and his 

 work was followed by a virtual blank of over fifty years. 



MODERN EXPLORATION. 

 James O. Pattie was the first of more recent explorers to reach the head of the Gulf. 

 He, with his party of trappers, journeyed down the lower Colorado to tidewater in January 

 1828, and during February of the same year they crossed the western part of the Delta, 

 the Cocopah Mountains, and the basin beyond, on their way to the Spanish settlement 

 at San Diego. 3 



1 British Museum, K. 118.32. A divided copy of this same map also exists in the library of the American 



Geographical Society, New York. 



2 An excellent reproduction of Font's map is to be found in The Diary and Itinerary of Francisco Garces, by 



Elliott Coues. New York, 1900. 

 The personal narrative of James O. Pattie, of Kentucky. Edited by Timothy Flint, Cincinnati, 1833. 



Fia. 1. — -Outline map of the head of the Gulf of 

 California and Salton Sink, according to Rocque. 

 (Plate fi.) 



