lithograph vs lithography

lithograph

noun
  • A printed image produced by lithography. 

verb
  • To create a copy of an image through lithography. 

lithography

noun
  • The process of printing an image by drawing the image with a water-repellent material onto a hard, flat surface (typically metal), then copying the surface by applying water and ink (or the equivalent) to it and pressing another material against it. 

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