ciphering vs summation

ciphering

noun
  • A cipher (fault in an organ valve which causes a pipe to sound continuously without the key having been pressed). 

summation

noun
  • summarization; summary; summing up. 

  • summing; summing up; adding (adding up) of a series of items. 

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