VALLEYS AND PLAINS — WATER COURSES. U 



westerly direction close under the former mountain. In its course tliis stream flows through 

 a gorge for about twelve miles, separating the main valley into the upper or Santa Inez valley, 

 and the lower or La Purisima, from the mission there located. These valleys have a com- 

 bined length of fifty miles and an average width of four miles, and are bounded on the 

 north by terraces sloping back to low spurs jutting out from the mountains to the coast. The 

 valleys and side slopes of the mountains and terraces are dotted with clumps of oaks, and the 

 streams fringed with a growth of willow and cotton-wood. Leaving the Santa Inez, no valley 

 is found until arriving at the mission of Santa Buenaventura, which is situated at the mouth of 

 the valley of the same name, near the beach. This we crossed at right angles, but found, by 

 side explorations, that it extends inland, and turning the east end of the Santa Inez mountain, 

 heading with the Santa Inez river, receives the waters of the ocean slope of a lofty ridge, the 

 extension of the Santa Lucia which separates this valley from the head of the Cuyama plain. 

 Leaving the San Buenaventura, we enter upon the Santa Clara plain, which takes its name 

 from the stream draining it. This plain extends from the beach, where its width is twenty miles, 

 inland for forty miles, gradually narrowing as it is ascended, and contains nearly two hundred 

 square miles. It heads in the New or Williamson's Pass, and in a range of mountains behind the 

 mission of San Fernando, and is joined in its course by several tributary valleys. It is separated 

 from the San Fernando plain by the Santa Susana mountains, within which, however, lies a 

 small valley, the Semi, apparently completely cut off from the plain on either side, but is a 

 tributary of the Santa Clara, and from its location and extent affords an easy connecting link 

 between the two plains. The San Fernando has an area of eighty-five square miles, bounded on 

 the north by a high ridge or main axis of the Coast Kange^, on the west by Santa Susana, and 

 separated from the ocean by a low rolling ridge, which extends for thirty miles to Los Angeles, 

 where the stream which receives all the waters of the plain and surrounding slopes turns the 

 ridge and bears off to the ocean at San Pedro. Between Los Angeles and the coast, and adjacent 

 to the stream above noted, there is spread out another smooth extent of prairie or meadow 



country containing about square miles, the Los Angeles plain proper. To the east, and 



at the base of the mountains is found the mission of San Gabriel, located upon the foot slopes 

 of the mountain range, and overlooking another large plain, bearing the name of the mission. 

 These are simply local names and are all embodied under the general name of Los Angeles 

 plains, embracing the champaign district lying at the base of the mountains between the 

 missions of San Fernando and San Gabriel, and extending oS to the shore line. But it must 

 not be understood as one unbroken and continuous prairie surface. It is beautifully diversified 

 witli smooth knolls and low rolling ridges, with an occasional clump of oaks near the base of 



the mountains. 



Section 4. WATER COURSES. 



The Coast Eange between the Bay of San Francisco and the plains of Los Angeles is drained 

 by numerous small streams, which break from the caiions and gorges, clear limpid mountain 

 brooks, whose waters become turbid and sluggish as they meander through the lower valleys 

 and plains, and are often entirely absorbed by the sands of their beds. In the mountainous 

 districts these streams have narrow valleys and gorges while flowing parallel with the geological 

 axis. But when these axes are crossed or ridges pierced the valleys become contracted, till 

 finally the stream is hemmed in by lofty walls of rock approaching verticality, and flows over a 

 bed of huge boulders, rendering the passage of these caiions always difficult, and often 

 impracticable. As soon as these streams debouch upon the plain districts their features undergo 

 2 T 



