conceal vs perspire

conceal

verb
  • To hide something from view or from public knowledge, to try to keep something secret. 

perspire

verb
  • To emit (sweat or perspiration) through the skin's pores. 

  • To be evacuated or excreted, or to exude, through the pores of the skin. 

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