David Graham Phillips 
The Grain of Dust: A Novel [PDF ebook] 

Phillips was an American investigative journalist and author, whose concern with the social issues of the day earned him the reputation of a ‘muckraker.’ His writing ultimately led to his untimely death when he was shot dead by a musician who had taken exception to one of his works.
The book sold well enough that his royalty income was sufficient enough to allow him to work as a freelance journalist while dedicating himself to writing fiction.