descending vs feathering

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. 

feathering

noun
  • Plumage. 

  • The fitting of feathers to arrows. 

  • Visible offshoots of the trails of ink written on overly absorbent paper. 

  • A feathered texture. 

  • An arrangement of small arcs or foils separated by projecting cusps, frequently forming the feather-like ornament on the inner mouldings of arches. 

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