decussation vs trave

decussation

noun
  • A crossing or intersection of lines etc. so as to form an X-shape. 

trave

noun
  • A section formed by crossbeams. 

  • A wooden frame to confine unruly horses while they are shod. 

  • A crossbeam. 

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