labor-saving vs logical

labor-saving

adj
  • Making work easier or faster. 

logical

adj
  • Of or pertaining to logic. 

  • In agreement with the principles of logic. 

  • Relating to the conceptual model of a system rather than its physical expression 

  • Reasonable. 

How often have the words labor-saving and logical occurred in a corpus of books? (source: Google Ngram Viewer )