shallows vs whirlpool

shallows

noun
  • An area in a large body of water with many shallow areas. 

whirlpool

noun
  • A swirling body of water. 

  • Turmoil, or agitated excitement. 

  • A hot tub, jacuzzi. 

verb
  • To spin or swirl like the water in a whirlpool. 

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