lather vs quirt

lather

verb
  • To beat or whip. 

  • To form lather or froth, as a horse does when profusely sweating. 

  • To cover with lather. 

noun
  • A state of agitation. 

  • The foam made by rapidly stirring soap and water. 

  • Foam from profuse sweating, as of a horse. 

quirt

verb
  • To strike with a quirt. 

noun
  • A rawhide whip plaited with two thongs of buffalo hide. 

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