grappling iron vs kedge

grappling iron

noun
  • A metal hook, attached to the end of a line, used to hold two ships together. 

kedge

noun
  • A small anchor used for warping a vessel. 

  • A glutton. 

verb
  • To move with the help of a kedge, as described above. 

  • To warp (a vessel) by carrying out a kedge in a boat, dropping it overboard, and hauling the vessel up to it. 

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