bolk vs eructate

bolk

verb
  • To belch. 

  • To belch out; give vent to; ejaculate. 

  • To vomit; retch. 

  • To heave. 

  • To gush out. 

eructate

verb
  • To burp; to belch. 

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