penitential vs reformatory

penitential

adj
  • Pertaining to penance or penitence 

noun
  • a book or set of rules pertaining to the Christian sacrament of penance 

reformatory

adj
  • Of, pertaining to, or conducive to reform; reformative. 

noun
  • A prison, especially one for juveniles; a reform school. 

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