. TOPOGRAPHY. 7 



about twenty-five hundred feet above the sea ; and then the 

 coniferous trees appear, and are found in dense forests to a 

 height of six thousand feet. 



11. Rivers of the Sierra. The low land of the Sacra- 

 mento basin, bounded on the west by the Coast Mountains 

 and on the east by the Sierra Nevada, which ranges meet both 

 at the north and the south, is the heart of the State, four hun- 

 dred miles long by fifty wide, reaching from latitude 35 to 

 40 30'. It is drained by two rivers : the Sacramento, run- 

 ning from the north ; and the San Joaquin, from the south. 

 They meet and unite in the center of the basin, at 38, and 

 break through the Coast range to the Pacific, forming, the 

 bays of Suisun, San Pablo, and San Francisco, on their way. 

 The valley is nearly level, and thirty feet above the level of 

 the sea at the junction of the rivers, and two hundred feet 

 higher where they issue from the mountains. Part of the Sac- 

 ramento Valley shows terraces, the farthest from the river being 

 a coarse gravel. The richest soil is on the immediate bank. 

 The great body of the valley is bare of trees. Its even surface 

 is broken in only one place, by the " Buttes," a range of vol- 

 canic hills, six miles wide by twelve long, with three peaks, 

 about two thousand feet high, which rise in lonely abruptness 

 from the middle of the plain, in 39 20'. The general course 

 of the two main rivers of the basin lies nearly midway between 

 the two mountain chains, but almost all their tributaries come 

 from the Sierra Nevada, which, like the Coast Range, has 

 most of its wealth on its western slope. In the four hundred 

 miles from Tejon to Shasta, there are a dozen creeks marked 

 on the map as flowing eastward from the Coast Range to the 

 San Joaquin and Sacramento ; but during the summer, three- 

 fourths of them are swallowed up in the sands before reaching 

 their mouths. Not one south of 38 is a permanent stream. 

 From the Sierra Nevada a number of rivers run westward. 

 Beginning at the north, we have the Pit, Feather, Yuba, 

 American, Cosumnes, Mokelumne, Calaveras, Stanislaus, 



