SALT AND SULPHUR SPRINGS.—SULPHUR. 2} 
bonate of lime, a little magnesia and alumina, with traces of oxide of iron. A large insoluble 
residue remains. The specimen is apparently a remnant of a rock—probably a silicious lime- 
stone—altered by the action of sulphuric acid. 
Small salt ponds and dry lake-beds incrusted with white salt, are very common on the plains 
and valleys of California, especially in the vicinity of Tertiary strata. It is possible that some 
of the deposits Captain Pope observed have a similar origin; but there is no evidence in the 
collection of the existence of Tertiary formations. The drift deposit, which has been described 
by Doctor Shumard as covering the rocks of the Llano, may, and very probably does, belong to 
the age of the Tertiary; but the materials and facts that were procured by Captain Pope are not 
sufficient to warrant any conclusions on this point. 
Springs.—Other sources of these accumulations of saline water, and which appear to be very 
common in the region examined, are the springs at different points of the route, which, for 
volume and persistence of flow, are truly remarkable for that region, which is so arid and 
desert-like. Several of these springs are in direct connexion with salt lakes or ponds. The Ojo 
del Cuerbo has already been mentioned, and another example is found in the Big springs of the 
Colorado, which, according to Captain Taplin, ‘‘ issue from a ravine on the northeast slope of 
a range of hills 200 or 250 feet high, whose general direction is S. 45? E. Ata distance 
of one and a half mile, the outlet of the springs joins the valley of the salt lakes, and becomes at 
this point dry. Many of these lakes contain water; the beds when we passed being moist, and 
the water totally unfit for use.’’! 
He again observes, in relation to a valley about eight miles from the Mustang springs, that 
it contains at its northwest extremity a chain of salt lakes, ‘‘ which have a course a little south 
of east, their outlet passing only a mile and a half east of the Big springs of the Colorado, which 
are tributary to it." At the northern extremity of the same valley, the outlet to the Sulphur 
springs of the Colorado joins this chain of lakes. This Sulphur spring is described as ‘‘at 
least fifteen or twenty feet deep, and about twenty yards wide." 
Captain Pope's observations on the springs and lakes or ponds of Delaware creek, are inter- 
esting in this connexion. He describes the creek as a *ísuccession of small lakes, ten or 
fifteen feet deep, connected by a swift running stream.’ ‘‘It has its source in a limestone bluff, 
about fifty feet above its valley, and issues from the base of the bluff from seven or eight springs 
both pure and mineral. The largest of the pure springs bursts boldly out of the north side of 
the hill in a stream as large as a barrel, and, after a course of probably fifty yards, it unites with 
the small streams from the mineral springs. These springs contain sulphur in various propor- 
tions—in some barely perceptible, while in others it gives out an odor which is sufficiently 
. perceptible at fifty yards. There are six of these sulphur springs. From the south side of the 
bluff issues a spring strongly impregnated with soda, and all the springs uniting in one of the 
small lakes or ponds of Delaware creek form a compound detestable both in smell and taste. 
The animals, to my surprise, greatly preferred this lake to the pure water of the spring.’’? 
Prof. James C. Booth has made some interesting observations upon the specimens of the 
water from these springs, which were submitted to him by Captain Pope, and the results are 
found in the table appended to his report.) It appears that they contain very considerable 
quantities of sulphide of sodium and common salt. The earth which Captain Pope collected, 
and which had a sulphurous odor, I have had examined, and it was found to contain over 18 per 
cent. of sulphur.* Alumina, oxide of iron, lime, magnesia, and sulphuric acid were found in 
the aqueous extract. 
Captain Pope also describes the Independence springs, sixteen miles from the head of Dela- 
ware creek, as bursting out from the surface of the ground in a small valley or depression of 
the table-lands. There are two springs, and by their union they form a small stream, which 
becomes dry a few miles below. ‘‘These springs are about five feet in diameter, and, although 
? Report of Captain Pope, p. 30. 
! Report of Captain Pope, p. 78 
T A a 4 Bee description, under the head of ‘‘Sulphur.”’ 
* Report of Captain Pope, Appendix C, p. 95. 
