purify vs putrefy

purify

verb
  • To free from guilt or sin. 

  • To cleanse, or rid of impurities. 

  • To become pure. 

putrefy

verb
  • To corrupt; to make foul. 

  • To make morbid, carious, or gangrenous. 

  • To become filled with a pus-like or bile-like substance. 

  • To reach an advanced stage of decomposition. 

  • To become gangrenous. 

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