pen in vs send down

pen in

verb
  • To cause to be stuck in a situation; to be forced into a situation by circumstances. 

  • To enclose (animals) in a pen. 

  • To schedule; fix a date for. 

send down

verb
  • To cause something or someone to pass from a higher to a lower place. 

  • To demote a player within the levels of professional baseball. 

  • To bowl. 

  • To commit (someone) to a prison term. 

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