coal vs sooty

coal

verb
  • To burn to charcoal; to char. 

  • To supply with coal. 

  • To take on a supply of coal (usually of steam ships). 

  • To mark or delineate with charcoal. 

  • To be converted to charcoal. 

noun
  • A type of coal, such as bituminous, anthracite, or lignite, and grades and varieties thereof, as a fuel commodity ready to buy and burn. 

  • A glowing or charred piece of coal, wood, or other solid fuel. 

  • A black or brownish black rock formed from prehistoric plant remains, composed largely of carbon and burned as a fuel. 

  • A piece of coal used for burning (this use is less common in American English) 

  • charcoal. 

sooty

verb
  • To blacken or make dirty with soot. 

adj
  • Of the color of soot. 

  • Of, relating to, or producing soot. 

  • Soiled with soot 

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