Article snapshot taken from Wikipedia with creative commons attribution-sharealike license.
Give it a read and then ask your questions in the chat.
We can research this topic together.
Jack Williams was the name of two Old Westoutlaws. The first was hanged and the second, upon his appearance, became known as Jack William's Ghost or The Ghost Robber.
References
Roddy, W. Lee (1970). Wanted! Black Bart and Other California Outlaws. Ceres, California.{{cite book}}: CS1 maint: location missing publisher (link)