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Show 166 the perpendicular, and some strata are even inverted. Suddenly, immediatelyafter leaving the sandstone schist and dolerite, we find ourselves before a granite wall, which rises abruptly from 100 to 150 feet above the Tertiary rocks. This is the Sierra Madre, with its gray granite, consisting of fine particles, its pegmatite, its veins of quartz, it* green and micaceous schist, and its old diorites. All at once the Sau Fran-cisquito Canon, which until now has been pretty wide, except near the dike of dolerite, becomes narrow and very sinuous, like the granitic canons of San Gabriel, Tujunga, Pacoima, and Soledad. The directions of the crests or summits of the mountains also change abruptly, and instead of running from east to west, as in the San Fernando and Santa Monica Sierras, they run from south to north. Between Humphrey's ranch and the summit of the pass there are three parallel ranges of mountains running from south to north. The Delano ranch is situated in a little valley between the first and second of these ranges. After passing the valley of Lake Elizabeth we come to a fourth granitic range, known by the name of the Sierra de Liebre, which borders on the Calitornian Desert. These four ranges of the Sierra Madre are of unequal heights, the highest being in the locality where the " col" of the pass is found. The valleys which separate them, moreover, are of very different widths. The fir « t two are the narrowest, while the valley of Lake Elizabeth is comparatively wide and open. Origin of the name California.- Lake Elizabeth extends from east to west, and an extremely violent west wind blows there night and day, scarcely ceasing for a single instant ; it is a dry wind, and its heat, which reminds one strongly of the air of a hot oven, has evidently given rise to the name California. The Mexicans or Spauish- Americans, who first came to this country by laud via Sonora or New Mexico, soon remarked this temperature and this very peculiar climate, which has nothing in common with the three divisions which they had adopted, until that time, for Mexico, viz, tierra fria, tierra templada, and tierra caliente, i. e., cold country, temperate country, and warm conn-try ; and they very properly called this couutry, so different from the three others, tierra California, that is to say, country hot as an oven. SIERRA LIEBRE AND CALIFORNIA DESERT. After crossing the Sierra Liebre, which separates the valley of Lake Elizabeth from the great basin or California Desert, if we follow the east foot of this granitic sierra, we several times cross wide river- beds, which are hollowed out in the sand, and through which not even small brooks now run. These dry beds indicate that at no very distant day- for one would suppose that the water in them gave out ouly a few days ago- large rivers descended from the Sierra Madre, or rather from that part of the Sierra Madre which is called the Sierra Liebre, discharging their waters into the great valley of the Dry Lake, where is now Willow's Station. The climate of Southern California has evidently undergone great changes in modern times. The sand of the desert covers this entire basin, which is a genuine American Sahara. Nevertheless, two miles to the east, before reaching Liebre's ranch, we again meet with the Tertiary sandstone, with the conglomerate, which here forms a counterfort to the Sierra de Liebre. The strata dip to the south- southeast and north- northwest, at an angle varying from 15° to 30°, showing here and there the synclinal line of the strata. These saud-stone rocks, which are of a gray and sometimes of a reddish color, are seen all along the road from Liebre ranch as far as Gorman's ranch, at the entrance of the cation of Fort Tejon or Cafiada de las Uvas. I was unable to determine the exact age of these Tertiary rocks, in consequence of a very long and painful journey in the month of July, when the weather was excessively hot. It is possible that some of the strata are of the Miocene epoch; I am, however, rather inclined to regard them as Eocene rocks. Where was the strait or passage through which the Tertiary sea communicated from west to east across the Sierra Madre and the Sierra Nevada f I have not been able to recognize it. It was evidently neither through the San Franoisquito Pass, nor the Canada de las Uvas or canon of Fort Tejon, nor through the Tehachipi Pass. The Tejon Pass is the only one which I have not visited, but toward this all the Tertiary rocks to the east and west of the pass seem to run; and it was probably through this pass that the Tertiary sea, which covered the entire western portion of California, penetrated across the granitic chains into the great basin of the California Desert. This communication, owever, possibly took place through the valley of the Rio de Peru, the water pawing by the south foot of Mount Pinosand flowing into the great basin in the comparatively low mountains which are found between Liebre ranch and Gorman's ranch. Canada de las Uvas.- The Tertiary rocks in the vicinity of Gorman's ranch, which are very much uplifted and which dip to the west toward the Sierra de Liebre at an angle of 60°, are crossed by dikes of doled tea and euphotides, the real gabbro of Tuscany. The summit of the pass of the Canada is on these euphotides, with yellow sandstones, and Tertiary, whitish, limestones. As soon as we descend we come to the granite of the range, which runs to the east of Lake Castac; and then the entire canon of Fort Tejon runs through the granitic and crystalline rocks, gneiss; and a mile and a half this side of Fort Tejon we find a large dike of grayish- white crystalline limestone, |