ignite vs turn off

ignite

verb
  • to spark off (something), to trigger 

  • to commence burning. 

  • to set fire to (something), to light (something) 

  • To subject to the action of intense heat; to heat strongly; often said of incombustible or infusible substances. 

turn off

verb
  • To become deactivated; to become powered down. 

  • To repulse, disgust, or discourage (someone). 

  • To leave a road; to exit. 

  • To power down, to switch off, to put out of operation, to deactivate (an appliance, light, mechanism, functionality etc.). 

  • To rotate a tap or valve so as to interrupt the outflow of liquid or gas. 

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