BERNARDINO SIERRA-—YUCCA TREE—BRECCIA. 55 
appears to be prolonged to the westward of the end of the Sierra Nevada, and forms the south- 
ern end of the Tulare valley, perhaps extending to Point Conception on the coast, this being in 
the line of trend. The direction of this chain is, therefore, nearly transverse to the general 
direction of the Sierra Nevada, and it has already been noted as the transverse chain. Although 
this difference in the direction of the two chains is not very apparent to the observer when in 
the Cañada de las Uvas, or when travelling southwards from the Tulare valley to Los Angeles 
or the San Francisquito Rancho, it becomes very striking when he passes out upon the surface 
of the Great Basin, and can view the Sierra Nevada and the transverse chain at the same time. 
The Sierra Nevada, when seen from the Basin, appears to extend in a meridional direction and 
to be joined by the other chain at right angles. As the peaks and ridges of the transverse 
chain are not covered with snow except in the winter, it cannot be included with the Sierra 
Nevada, and known under the same name. It is also separated or made distinct from the Sierra 
by its direction, and from the ranges called ‘‘ Coast Mountains,” both by position and geological 
structure. The rocks composing it are similar to those of the Sierra Nevada, and it should be 
regarded as a prolongation of that chain, and not of the Coast Mountains. As the most promi- 
nent and well known peak of the transverse chain is named San Bernardino, I shall refer to the 
chain in the succeeding descriptions as the Bernardino Mountains or Bernardino Sierra, mean- 
ing the east and west ranges of mountains between San Bernardino and the end of the Tulare 
valley, or beyond, to the western limit of the granitic rocks. 
PASS OF SAN FRANCISQUITO. 
The entrance or approach to the Pass of San Francisquito from the surface of the Great Basin 
is not marked by any peculiar or striking topographical feature. The outline of the mountains 
is very uniform, and not marked by any great depression or high peaks. It is, however, very 
probable that a long ridge which intervenes between the Basin and the main ridge of the 
mountains hides the full outline from view. The slope of the Basin is very regular, and rises 
without any great undulation from the dry lake or hard clay surface at the lowest point of that 
part of the Basin to the foot-hills of the pass. This slope is dotted on its upper portion by the 
thorny yucca tree, which here and there forms thick clumps or groves, or they stand singly, 
rising to the height of a man, and bearing such a close resemblance to men in size and position, 
that they often deceive one for a moment when they are viewed from a distance. 
Foot-hills of the mountains,—Remarkable brecciated strata of volcanic rocks. —The first hill or 
rise of the surface, near the entrance to the pass, stands alone, as it were, about five miles dis- 
tant from the main mass of mountains, and is separated from them by a continuation of the 
Basin-slope. This hill rises to an altitude of about 300 feet above the slope, and is composed 
of highly inclined strata, very regularly stratified, trending north 30? east, with a north-west- 
ward dip. The lower parts of the hill are composed of sandstone strata of a light color, but 
the higher portions consist of remarkable beds of volcanic materials, regularly stratified, but 
dipping with the sandstone. These beds contained porphyries of great beauty, in large blocks 
and boulders, all firmly united together. 
! For a note explanatory of the use of the word Sierra, see Chapter XI. 
