hot-air balloon vs soar

hot-air balloon

noun
  • A balloon-shaped aircraft whose bag is inflated with hot air; it carries passengers and crew in a gondola slung underneath. 

soar

noun
  • An upward flight. 

  • The act of soaring. 

verb
  • To rise, especially rapidly or unusually high. 

  • To mount upward on wings, or as on wings, especially by gliding while employing rising air currents. 

  • To rise in thought, spirits, or imagination; to be exalted in mood. 

  • To remain aloft by means of a glider or other unpowered aircraft. 

  • To fly high with little effort, like a bird. 

How often have the words hot-air balloon and soar occurred in a corpus of books? (source: Google Ngram Viewer )