froth at the mouth vs ptyalize

froth at the mouth

verb
  • To spew saliva as froth. 

  • To rage, to vent one's anger. 

ptyalize

verb
  • To salivate. 

  • To spit. 

How often have the words froth at the mouth and ptyalize occurred in a corpus of books? (source: Google Ngram Viewer )