preserver vs salvager

preserver

noun
  • A person who prepares preserves of fruit or preserved meats. 

  • A person who refinishes furniture. 

  • One who preserves. 

  • A life preserver. 

salvager

noun
  • A person who engages in salvage work 

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