photoengraving vs transferring

photoengraving

noun
  • A plate or reproduction made using this process. 

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

transferring

noun
  • The act by which something is transferred; a transfer. 

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