bass viol vs gamba

bass viol

noun
  • A fretted, bowed, stringed musical instrument from the viola da gamba family. It occupies the bass range and is the lowest instrument in the family. Similar to (but smaller than) a cello. 

gamba

noun
  • A rank of organ pipes, so called for a supposed resemblance of the sound to that of a viola da gamba. 

  • The metacarpus or metatarsus of ruminants, etc. 

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