countervail vs equibalance

countervail

verb

  • To counteract, counterbalance or neutralize. 

  • To compensate for. 

equibalance

verb

  • To make of equal weight; to counterbalance. 

noun

  • Equal weight; equiponderance. 

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