knout vs rawhide

knout

verb
  • To flog or beat with a knout. 

noun
  • A leather scourge (multi-tail whip), in the severe version known as 'great knout' with metal weights on each tongue, notoriously used in imperial Russia. 

rawhide

verb
  • To beat with a rawhide whip. 

  • To clear (a pump) of sediment by starting and stopping it repeatedly. 

noun
  • Untanned hide. 

  • A whip made from twisted untanned leather. 

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