obscene vs pure as driven snow

obscene

adj
  • Offensive to standards of decency or morality. 

  • Disgusting or repulsive. 

  • Lewd or lustful. 

  • Liable to corrupt or deprave. 

  • Beyond all reason; excessive. 

pure as driven snow

How often have the words obscene and pure as driven snow occurred in a corpus of books? (source: Google Ngram Viewer )