Aaah, my fellow Twainiacs, Hyde vs. Morgan is one of Twain's better  
stretchers. Fiction from start to finish. But like the "Genuine Mexican Plug"  
(Tom Nye's "razor-back" horse of an Enterprise letter) not without a  general 
sort of source.
 
At some unknown date in the wayback machine, a huge piece of a mountain did 
 slide down into Washoe valley, creating what is called "Slide Mountain." 
The  huge gouge stands out today. It is a cliff above a broad valley of the 
sort that  hang gliders love. 
http://www.alllaketahoe.com/parks/washoe_lake_state_park.php
 
From time to time, slides do still occur, and one during the 1850s damaged  
the overland trail branch down from the Truckee River route. There were 
also  notorious snowslides that piled snow deep at the base of the slide. Most  
recently, the failure of a small dam in the 1983 caused a major slide  
there.
 
According to Myra Ratay in Pioneers of the Ponderosa, Dick Hyde  was Dick 
Sides, who, she says, lived at Franktown, well south of the slide. Dick  
Morgan was fictional if the Census is any authority. 
 
I think Twain chose the name "Hyde" because of Mormon leader Orson  Hyde 
and the Mormon settlers who lived at Washoe City, north of the slide  detritus 
area, and were recalled to Salt Lake City well before the  Clemens brothers 
arrived. There was no major earth movement there during Sam's  stay in 
Nevada, and definitely none that resulted in a lawsuit with the clever  beauty 
of Twain's Hyde vs. Morgan. Probate Judge Orson Hyde laid his Mormon  curse 
on the valley in 1857 before returning to the City of Saints. I used to  
commute through the valley daily, and in winter we would occasionally joke about 
 being subjected to Hyde's curse when the snow was a small blizzard making 
the  freeway through the middle of the valley hazardous chains-only driving.
 
Marion Ellison's book of the Carson County Utah Territory court cases has  
no mention of such a lawsuit, and her husband, Bob, the go-to guy on early  
Carson County, UT, People and History (Bob and Marion are both Mormon)  
agrees it is a fabrication, perhaps Twain bringing Hyde into the book, and yes,  
taking a poke at Atty. Gen. Benjamin B. Bunker, who Lincoln removed from 
office  in June, 1863 for non-attention to duty and frequent absence from the  
Territory. [see 
http://poetry.rapgenius.com/Abraham-lincoln-the-papers-and-writings-of-abraham-lincoln-vol-vi-chap-2126-lyrics#lyric ]
 
Bob Ellison and I have both looked for California newspaper  (CDNC.ucr.edu) 
references to a mock trial, &c. Present day Nevada  historians [names and 
example on request] agree that Effie Mona Mack, cited  in the notes in Mark 
Twain Project's edition of Roughing It [UC  Press, 1993],  is not a good 
source for any serious scholar, though  her students loved her. 
 
Bob Stewart
 
 
 
In a message dated 10/13/2013 1:15:20 P.M. Pacific Daylight Time,  
[log in to unmask] writes:

I'm just  curious if this was something that actually occurred or just
another  stretcher from Twain's imagination.  I know that at least a  few
Twain-L subscribers have more than a passing knowledge of the history  of
Nevada Territories and its early statehood.  (Chapter 34 from  Roughing
It).