hairpiece vs periwig

hairpiece

noun
  • A false substitute for a person's hair; a toupee or wig. 

periwig

noun
  • A wig, especially any kind of stylised wig as formerly worn by men and women. 

verb
  • To dress with a periwig, or with false hair; to bewig. 

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