lum vs smokestack

lum

noun
  • A ventilating chimney over the shaft of a mine. 

  • A chimney; also, the top part of a chimney. 

  • A deep pool, especially one in a riverbed. 

  • A grove or wood; also, a woody valley. 

smokestack

noun
  • A conduit or group of conduits atop a structure allowing smoke to flow out, as on a steam locomotive, ship, factory, or power plant using fossil fuels. 

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