cross one's fingers vs supplicate

cross one's fingers

verb
  • when wishing for luck, or 

  • when telling a lie (and attempting to escape the moral and other consequence of that lie). 

  • To put the middle finger across the index finger, especially 

supplicate

verb
  • To humbly request for something, especially to someone in a position of authority; to beg, to beseech, to entreat. 

  • To make a humble request to (a deity or other spiritual being) in a prayer; to entreat as a supplicant. 

  • Of a member of the university, or an alumnus or alumna of another university seeking a degree ad eundem: to formally request that an academic degree be awarded to oneself. 

  • To make a humble request to (someone, especially a person in authority); to beg, to beseech, to entreat. 

  • To ask or request (something) humbly and sincerely, especially from a person in authority; to beg or entreat for. 

How often have the words cross one's fingers and supplicate occurred in a corpus of books? (source: Google Ngram Viewer )