adding machine vs computer

adding machine

noun
  • A simple mechanical or electromechanical calculator that could only perform simple calculations such as addition or subtraction 

computer

noun
  • A programmable electronic device that performs mathematical calculations and logical operations, especially one that can process, store and retrieve large amounts of data very quickly; now especially, a small one for personal or home use employed for manipulating text or graphics, accessing the Internet, or playing games or media. 

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