Geol— Vol. I.] DAVIDSON— SUBMERGED VALLEYS. 83 



in about 15 to 20 miles. There are three large streams 

 coming from the San Luis Rey Mountains, with a general 

 direction normal to the coast. 



3. The Newport Submerged Valley. 



The high hills of 1,000 feet elevation westward of San 

 Juan Capistrano, at the eastern approach to San Pedro 

 Channel, break down almost completely in longitude 117° 

 53' west, 22 miles east of San Pedro; and a large lagoon, 

 now called Newport Bay, extends three or four miles inland, 

 under the western flank of these hills. 



There is deep water close to the shore, abreast the hills, 

 200 fathoms, within 3^ miles, as if a broad submerged 

 valley were heading in toward the bay. A low, narrow, 

 sandy peninsula extends nearly three miles in front of the 

 bay, and at the western part of this peninsula a submerged 

 valley reaches in close to the beach with 25 fathoms. It is 

 well marked but not extensive, and reaches only to the 

 70-fathom line. West of it the broad 25-fathom plateau 

 extends to San Pedro. 



The geographical position of the head of this submerged 

 valley is in latitude 34° 36^' N., longitude 117° 56' W. 



On the plateau inside of 25 fathoms, the bottom is fine 

 gray sand, and occasionally mud; green mud and sand at 

 100 fathoms, and at greater depths brown mud. 



A large wharf was built here under the writer's location, 

 and this valley has protected it from storms for eight years. 



4. Santa Monica Bay. 



This broad bight or gulf is 25 ^/^ miles wide between Point 

 Vincente at the E. SE., and Point Dume at the W. NW., 

 and ten miles deep at the town of Santa Monica, nearly 

 equidistant from the two points. 



The shores of this bight have marked characteristics. 

 Point Vincente is the western rocky terminus of the isolated 

 San Pedro Hill, 1,493 feet high, and well marked with old sea 



