chela vs man Friday

chela

noun
  • A pincer-like claw of a crustacean or arachnid. 

  • A pupil or disciple, especially in Hinduism. 

man Friday

noun
  • A native or aborigine, especially one who inhabits an island 

  • A right-hand man 

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