Dart vs Mole

Dart

name
  • A river in Devon, England, which flows from Dartmoor to the English Channel at Dartmouth. 

  • A town in Ontario, Canada 

  • A surname from Middle English. 

noun
  • An officer trained at Britannia Royal Naval College, Dartmouth, England. 

Mole

name
  • A river in Devon, England, tributary to the Taw. 

  • A river in Surrey, England, tributary to the Thames. 

  • A surname. 

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