Geology and Mineralogy. 57 
n 
of the river and the underlying rock strata through which it has 
cut its way. The Klamath drains an immense extent of moun- 
tainous country, through which passes the great auriferous belt of 
California, as evidenced by the rich quartz leads and placer mines 
on the tributaries. Being a swift and deep stream, great quanti 
ties of water-worn gravel are swept down by the resistless floods 
of winter. These form at present as gravel bars, increasing in ex- 
tent toward the mouth, all more or less auriferous, and their 
presence can be easily accounted for. A remarkable distinction 
sphere, the grinding action being equal on all sides. On the 
el. 
is solution can be found on observation of the rock strata 
forming the river bed and cropping out on the sides. Commencing 
les as you ascend. is section, although the gravel bars 
forme the present action are frequent, yet no old deposits are 
found on the banks the end of this stretch of fifteen 
rock at these rapids is a hard talcose slate or serpentine. This fact 
