gallet vs lay open

gallet

verb
  • To use this masonry technique. 

noun
  • A splinter of stone inserted into the wet mortar of masonry. 

lay open

verb
  • To open (something) through cutting or scissoring. 

  • To expose or reveal (something). 

  • To publish a patent for initial public review, prior to the formal application for registration. 

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