cattle prod vs spur on

cattle prod

verb
  • To goad or push someone to act. 

noun
  • Something used to goad or push someone to act. 

  • A stick designed to goad cows, steers, and similar animals in order to prompt them to move in a desired direction, now usually electrified to administer a stimulating shock to the animal. 

spur on

verb
  • To spur or urge (someone) to do something. 

How often have the words cattle prod and spur on occurred in a corpus of books? (source: Google Ngram Viewer )