beat one's meat vs play with oneself

beat one's meat

verb
  • To masturbate by stroking or rubbing one's penis. 

  • To waste time; to engage in an unproductive activity. 

play with oneself

verb
  • To masturbate. 

How often have the words beat one's meat and play with oneself occurred in a corpus of books? (source: Google Ngram Viewer )