blueprint vs photoengraving

blueprint

noun
  • A type of paper-based reproduction process producing white-on-blue images, used primarily for technical and architecture's drawings, now largely replaced by other technologies. 

  • A print produced with this process. 

  • A detailed technical drawing (now often in some electronically storable and transmissible form). 

  • Any detailed plan, whether literal or figurative. 

verb
  • To make a blueprint for. 

  • To make a detailed operational plan for. 

photoengraving

noun
  • A process of transferring a photographic image onto a plate which is then etched and printed. 

  • A plate or reproduction made using this process. 

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