Im not absolutely sure but I think you can see one in a Mark Twain book.
Mark Twain could not continue as a riverboat navigator because of the Civil War.
"Twain" is an archaic term that means "two" or "between two." It's commonly known from the phrase "Mark Twain," which was used as a nautical term for water depth measurement. "Mark Twain" means the water is at a depth of two fathoms or 12 feet, indicating safe passage for boats.
Mark Twain's real name was Samuel Langhorne Clemens. His pen name, "Mark Twain," was derived from a riverboat term meaning "two fathoms deep." Another nickname he had was "The Father of American Literature."
Autobiography of Mark Twain was created in 1924.
Mark Twain House was created in 1874.
Mark Twain's nickname was actually his pen name; his real name was Samuel Clemens. He chose the name "Mark Twain" from a riverboat term meaning the water is two fathoms deep, indicating it was safe to navigate.
Mark Twain Memorial Bridge was created in 1936.
Mark Twain's Library of Humor was created in 1888.
Mark Twain State Park was created in 1924.
Mark Twain Birthplace Cabin was created in 1835.
Mark Twain Prize for American Humor was created in 1998.