equable vs of a piece

equable

adj
  • Not easily disturbed; tranquil. 

  • Unvarying, calm and steady; constant and uniform. 

  • Free from extremes of heat or cold. 

of a piece

prep
  • Used other than figuratively or idiomatically: see of, a, piece. 

  • Of the same kind. 

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