clout nail vs rail spike

clout nail

noun
  • Any of various types of nails with large flat heads designed to fasten sheet metal to wood, fasten clouts to axletrees, etc., often clinched. 

rail spike

noun
  • A type of large nail with an offset head used to fasten a rail or base plate to a wooden railroad tie/sleeper. 

How often have the words clout nail and rail spike occurred in a corpus of books? (source: Google Ngram Viewer )