by hand vs involuntary

by hand

prep
  • Without suckling it. 

  • Manually; without the use of automation or machines. 

involuntary

adj
  • Not voluntary or willing; contrary or opposed to explicit will or desire; unwilling. 

  • Without intention; unintentional. 

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