eyecap vs pair of eyeglasses

eyecap

noun
  • The brille of a snake. 

pair of eyeglasses

noun
  • A pair of lenses set in a frame worn on the nose and ears in order to correct deficiencies in eyesight or to ornament the face. 

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