black man vs mourning

black man

noun
  • Used other than figuratively or idiomatically: see black, man. 

  • A male adult member of an ethnic group having dark pigmentation of the skin, typically of sub-Saharan African descent; or the appearance thereof. 

mourning

noun
  • The traditional clothes worn by those who mourn (in Western societies, typically coloured black). 

  • Feeling or expressing sorrow over someone's death. 

  • The act of expressing or feeling sorrow or regret; lamentation. 

  • Drapes or coverings associated with mourning. 

How often have the words black man and mourning occurred in a corpus of books? (source: Google Ngram Viewer )