allay vs pacificate

allay

verb
  • To make quiet or put at rest; to pacify or appease; to quell; to calm. 

  • To alleviate; to abate; to mitigate. 

noun
  • Alleviation; abatement; check. 

pacificate

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