Echo vs Zodiac

Echo

name
  • 60 Echo, a main belt asteroid. 

  • An oread, punished by Hera by losing her own voice and only being able to mimic that of others. 

Zodiac

name
  • a family of constellations that are visible in the apparent path of the Sun viewed from the Earth over the year 

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