chimney stack vs volcano

chimney stack

noun
  • A vertical structure, normally of brick, rising from a roof, containing one or more flues, each one terminating in a chimney pot. 

volcano

noun
  • A kind of firework producing an upward plume of sparks. 

  • A vent or fissure on the surface of a planet (usually in a mountainous form) with a magma chamber attached to the mantle of a planet or moon, periodically erupting forth lava and volcanic gases onto the surface. 

verb
  • to erupt; to burst forth 

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