DEPARTMENT OF BOTANICAL RESEARCH. 59 



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 Avas evidently the true gateway from the interior to the Pacific 

 Ocean. The discovery of this practicable and easy railway route determined 

 the construction of a southern railroad, and made it necessary to acquire 

 from Mexico the strip of country in southern Arizona since known as the 

 "Gadsden Purchase." 



We descended with eagerness into this great unknown valley, carefully 

 reading the barometer at regular distances to ascertain the grade. Pro- 

 ceeding without obstacles, but without any trace of a road, and following 

 the dry bed of a stream, now known as the Whitewater, we reached the 

 bed of a former lake and found it to be below the level of the sea. 



The accumulation of salt in the lowest part of the desert was well known 

 to the Cahuilla Indians, who had resorted to it for salt for an unknown period. 

 Being a little off the trail or road then traveled from Yuma to the settle- 

 ments in California, it was not often visited or seen by the early explorers, 

 who, after the long journey of 90 miles without water, pressed forward 

 without delay to the shades and springs of potable water on the seaward 

 slope of the mountains at Warner's Ranch. 



Emory, 1848, mentions the salt lake as three-quarters of a mile long and 

 half a mile wide, and that the water had recedecl to a foot in depth. The 

 salt-bed was not conspicuous in 1853, at the time of Williamson's survey. 

 Its precise position was not ascertained. It was said that it was sometimes 

 flooded with Avater, which was supposed to have reached it from the over- 

 floAV of the Colorado, through the channel of New Piver. 



Geographical Features of the Cahuilla Basin, hy Godfrey Sykes. 



Mr. Sykes has been a member of nearly all of the overland and 

 water expeditions made in the Desert of the Colorado by the force of 

 the Desert Laboratory, and has prepared two sketch maps showing 

 the principal geographic features of interest in connection with the 

 studies of the Cahuilla Basin. Routes and observation stations are 

 located with accuracy. A systematic search has been made in the 

 principal collections of old maps in America and England for records 

 which might suggest changes in the delta of the Colorado and in the 

 Salton Sink in the last 250 years. In addition to the acquisition of 

 valuable information upon the history of exploration of the region, it 

 has been discovered that a map by Rocque (17G2?) show^s the Colo- 

 rado River flowing into a body of water to the northwestw^ard of the 

 head of the Gulf of California in the position occupied by the Salton 

 Sink. A similar feature is suggested on other maps of that time. 



The Geology of the Cahuilla Basin, by E. E. Free. 

 This paper summarizes all available information concerning the 

 geology of the Cahuilla region, with especial reference to the history 

 of the lake which previously occupied the basin and which has been 

 named "Blake Sea." The major conclusions are (1) that this lake 

 was fresh, (2) that it was quite recent, and (3) that it was either 

 formed by the Colorado River or greatly modified by the inflow^ of 



