87(3 PROCEEDINGS OF THE CALIFORNIA 



prominent minerals occurring as such in other mineral regions, namely, fluor ; 

 to which it may be added, that both calcite and barytes are extremely rare as 

 veinstones in California, and to judge from all the Mexican and Chilean col- 

 lections that I have seen, well crystallized specimens are very rare in those 

 countries. 



8th. There is no elementary substance, and but few mineral species peculiar 

 to the Pacific coast, so far as yet ascertained. 



Professor Whitney remarked on the depression of Death Valley, 

 the sink of the Amargosa River, below the level of the sea. Re- 

 cently it has been repeatedly stated in the newspapers that no such 

 depression really existed, and that, in point of fact, the valley in 

 question was several thousand feet above the sea level, Mr. Gabb 

 being cited as authority. 



The valley visited by Mr. Gabb, however, was not, it appears, the 

 real Death Valley, but one to which that name was given by an 

 explorer by mistake. The true Death Valley is the sink of the 

 Amargosa, while the one visited by Mr. Gabb is near the head of 

 that river. The barometrical observations on which the statement 

 of the depression of the real Death Valley is based were taken, in 

 1861, by a party of the California Boundary Survey. The observa- 

 tions were made with a barometer, which was compared before and 

 after being used, with a standard, by Colonel R. S. Williamson, 

 by whom also the computations and reductions of the observations 

 Avere made ; there was also a station barometer at the time on the 

 Colorado, at no great distance, and this instrument was in good 

 order. Thus it will be seen that the conditions were, in most 

 respects, exceptionably favorable for a correct measure of the alti- 

 tude of the valley, and it may be safely assumed that its depression 

 below the sea level is not far from one hundred and seventy-five feet, 

 as stated on Colonel Williamson's authority, in the Geology of Cali- 

 fornia, Vol. I. To secure a more reliable result, it would be neces- 

 sary to have a long series of observations taken there with a well- 

 adjusted instrument, and it would be desirable also to have a station 

 barometer on the Colorado, or at some other not too distant point. 

 It will probably be a long time before these favorable conditions are 

 secured ; and, in the meantime, Col. Williamson's result must be 

 received as a close approximation to the actual amount of the 

 depression of this very remarkable locality. 



