Arthur Hall 
Secret Assassin [PDF ebook] 

The body lying on its back before us was unquestionably that of the man who had attempted to kill Holmes and I with explosives, at Glenbury Gardens. He wore the same dark clothing, although his hat was gone, and the hare lip was a livid scar on his pallid face. Strangely, it crossed my mind that what could be seen of his expression in death was softer than that he had worn in life.