keep in reserve vs lay by

keep in reserve

lay by

verb
  • To tend (a crop) for the last time, leaving it to mature without further cultivation. 

  • simple past tense of lie by 

  • (of a sailing vessel) To remain stationary while heading into the wind; to come to a standstill; heave to; lay to. 

  • To put away for future use; save; to build up as savings. 

How often have the words keep in reserve and lay by occurred in a corpus of books? (source: Google Ngram Viewer )