250 QUlGKSILVKIt DEPOSITS OF TUE PACIFIO SLOPE. 



between ranges which liad attained essentially their present configuration 

 prior to the formation of this sheet of water. 



The niaj), in accordance with the rules of the U. S. Land Office, shows 

 the outline of the lake at high water. The subaqueous contours are referred 

 as nearly as may be to the same level, or 10 feet above the lowest point 

 which the lake has reached in ten }ears. This point was noted by Capt. 

 R. S. Floyd, who has kept a full record of the level of tlie lake referred to 

 throughout this period. The lake occasionally rises a little more than 10 

 feet above low-water mark, but not enough to make any important differ- 

 ence. 



