Henry is right. Twain borrowed Orion's journal of the trip to write that  
section of Roughing It, so it has historical credibility some  other sections 
lack. They stayed in Salt Lake City two days, so that can be  subtracted 
from "road" time.
 
 
In a message dated 11/19/2014 8:34:55 A.M. Pacific Standard Time,  
[log in to unmask] writes:
 
The  University of California Press edition of Roughing It has a  detailed
chronology of the trip west, miles covered, locations and time on  pages
776-77.

Henry Sweets, Executive Director
Mark Twain Boyhood  Home & Museum
120 North Main Street
Hannibal  MO   63401
573-221-9010 extension  405