percolation vs soakage

percolation

noun
  • The seepage or filtration of a liquid through a porous substance. 

soakage

noun
  • The amount of liquid soaked in. 

  • The act of soaking. 

  • A source of water in Australian deserts, where water has seeped into the sand. 

  • food or nonalcoholic beverages consumed before or during a bout of drinking to slow down the onset of drunkenness 

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