Who was the first author to submit a book manuscript that had been written on a typewriter?

Mark Twain

Mark Twain became an early literary adopter of the typewriter and is often credited with submitting the first typewritten book manuscript. He later misremembered that book as The Adventures of Tom Sawyer; scholars identify Life on the Mississippi, copied from his handwritten manuscript in 1882, as his first typed literary manuscript and possibly the first.