gladius vs stylograph

gladius

noun
  • A pen, a hard internal bodypart of certain cephalopods, made of chitin-like material. 

  • A Roman sword roughly two feet long. 

stylograph

noun
  • A fountain pen that has a thin hollow tube or needle instead of a nib, and which releases ink when pressed against the paper. 

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