12 BORAX OF DEATH VALLEY AND MOHAVE DESERT, [bull. 200. 
north to northeast. Beyond this point the conditions are unknown. 
Mr. Spurr also reports that lake beds show at intervals along the road 
from Harper to Randsburg, nearly as far as Fremont Peak. North 
of the Santa Fe Railway the beds are disturbed, dipping generally to 
the south from 10° to 15°. Since the connection between these beds 
and the horizontal sediment about Victor has not been determined, it 
is uncertain whether they are of the same age or whether the tilted 
beds belong to the older or Eocene series. 
Daggett. — In order to obtain information regarding the eastward 
extent of these beds, the writer crossed from Victor to Daggett by 
the old stage road which runs by Stoddard Wells, 15 miles east of 
Mohave River. For a distance of 28 miles no lake beds were encoun- 
tered. The country is generally mountainous, the valleys are com- 
paratively narrow, and the rocks are either igneous or highly metamor- 
phosed sedimentaries. 
From Stoddard Wells the road follows a direct course N. 20° E. 
until it emerges into the valley of Mohave River 5 miles west of Dag- 
gett. A belt of Tertiary rocks having a width of about li miles is 
crossed by the road 4 miles south of this bend. The rocks are com- 
posed generally of fine clay and sand, containing a large amount of 
gypsum and other salts. Several thick beds of limestone were noted, 
which appear to have been the result of chemical deposition. The 
lower beds are composed of fragmental material; but in the upper 
part of the series occur many lava sheets which preserve the beds in 
high, even-crested ridges. This belt of rocks extends in a nearly east- 
west direction. The strata have been gently tilted along an axis run- 
ning in the same direction, so that they now dip to the north about 5°. 
The ridge formed by these beds appeared to extend westward for a 
distance of only a mile or two, and then to die out in the even expanse 
of desert which presumably extends to Mohave River. Toward the 
east the lake beds extend indefinitely. The question of the relation of 
these beds to the horizontal strata west of Mohave River is most inter- 
esting, and an examination of the western end of the beds just described 
might throw light on the relative age of these deposits. 
Heavy deposits of gravel occur on the northern slope of the Tertiary 
ridge. The} r rest upon the lake beds in such a manner as to suggest 
that the northward slope of the surface is a structural feature due to 
the tilting of a block of strata in that direction. If that is true, these 
lake beds probably underlie the Mohave River Valley in this vicinity. 
No borax was seen in this deposit, but the presence of other salts 
makes it seem probable that borax also is present. It was learned at 
Daggett that small deposits of borates occur there, but these reports 
were not verified. 
Borate. — The principal deposit of boron salts occurs at Borate, about 
12 miles north of Daggett, in the vicinity of the old Calico mining 
district. The mineral found here is borate of lime, or colemanite, 
