descending vs sinking

descending

noun
  • A descent. 

adj
  • Ordered such that each element is less than or equal to the previous element. 

  • Moving or sloping downwards. 

  • Becoming lower in pitch. 

  • Causing a sequence to follow a descending order. 

sinking

noun
  • The process by which something sinks, or is sunk. 

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