spotting scope vs spyglass

spotting scope

noun
  • A compact high-power monocular telescope optimized for detailed observation of distant objects such as wildlife or the strike of a bullet on a target. 

spyglass

noun
  • A small portable telescope. 

  • A pair of binoculars. 

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