conduit vs penstock

conduit

noun
  • A pipe or channel for conveying water, etc. 

  • A duct or tube into which electrical cables may be pulled; a type of raceway. 

  • A means by which something is transmitted. 

  • An investment vehicle that issues short-term commercial paper to finance long-term off-balance sheet bank assets. 

penstock

noun
  • A sluice or pipe which allows the controlled flow of water from behind a dam, typically routing it to a turbine of a power plant. 

  • The barrel of a wooden pump. 

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