brass nail vs scobs

brass nail

noun
  • Used other than figuratively or idiomatically: see brass, nail. 

  • A prostitute. 

scobs

noun
  • The dross of metals. 

  • raspings of wood, ivory, hartshorn, metals, or other hard substance 

How often have the words brass nail and scobs occurred in a corpus of books? (source: Google Ngram Viewer )