black as Newgate's knocker vs raven

black as Newgate's knocker

adj
  • Completely black in colour. 

raven

adj
  • Of the color of the raven; jet-black 

verb
  • To prey on with rapacity. 

  • To show rapacity; to be greedy (for something). 

  • To devour with great eagerness. 

noun
  • Any of several, generally large and lustrous black species of birds in the genus Corvus, especially the common raven, Corvus corax. 

  • A jet-black colour. 

  • raven 

  • Rapine; rapacity. 

  • Prey; plunder; food obtained by violence. 

How often have the words black as Newgate's knocker and raven occurred in a corpus of books? (source: Google Ngram Viewer )