contrivance vs invention

contrivance

noun
  • Something overly artful or artificial. 

  • A means, such as an elaborate plan or strategy, to accomplish a certain objective. 

  • A (mechanical) device to perform a certain task. 

invention

noun
  • Something invented. 

  • The capacity to invent. 

  • The act of inventing. 

  • A small, self-contained composition, particularly those in J.S. Bach’s Two- and Three-part Inventions. 

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