ballpoint vs dip pen

ballpoint

noun
  • A ballpoint pen. 

  • A kind of needle with a rounded tip. 

dip pen

noun
  • A kind of pen consisting of a nib with capillary channels like those of a fountain pen, mounted in a handle or holder. 

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