398 Adventures in Scenery 



Columnar Basaltic Lava in Walls 

 of Truck.ee Valley 



Beach gravel terraces, formed by the larger (Pleistocene) 

 Lake Tahoe, are all along Truckee River. Near Boca terraces 

 that were overflowed by basaltic lava show the columnar joint 

 structure in the walls of basalt. This columnar jointed struc- 

 ture is very characteristic of basaltic lavas. The jointing results 

 from shrinkage during the slow cooling of the lava. Ledges 

 of volcanic rock are exposed in many bluffs along Truckee 

 Canyon. The exposures are of many shades of color, light gray, 

 rusty, purplish, and dull green. The canyon is in places very 

 narrow and deep. Iceland is a small place that gets its name 

 from the industry which predominates at numerous places 

 along the canyon, viz., ice cutting. No natural ice is obtained 

 at lower levels in California, consequently on extensive business 

 has been built up in the production of ice in reservoirs formed 

 by dams in the canyon. 



Time to Return! 



Calvada is 229 miles from San Francisco, on the State line 

 of Nevada, at an elevation of 5,041 feet, and 14 miles farther 

 on is Reno. In the interest of domestic tranquillity it may be 

 well that we stop right here! 



ROUTE G. SACRAMENTO, VIA MARYSVILLE TO LASSEN 

 VOLCANIC PEAK AND MOUNT SHASTA. 256 MILES 



Roseville, 18 miles (El. 162 feet) ; Marysville, 52 miles (El. 

 72 feet); Chico, 95 miles (El. 193 feet); Tehama, 123 miles 

 (El. 223 feet); Redding, 213 miles (El. 557 feet); Mount 

 Shasta, 247 miles (El. 3,553 feet) ; Yreka, 291 miles (El. 2,624 

 feet) . 



The Sacramento Valley extends from Carquinez Strait, 

 through which the Sacramento and San Joaquin rivers reach 

 the ocean, north 160 miles to Redding. It embraces the vast 

 area between the Coast Range on the west and the Sierra 



