adhere vs cohere

adhere

verb
  • To be attached or devoted by personal union, in belief, on principle, etc. 

  • To affirm a judgment. 

  • To be consistent or coherent; to be in accordance; to agree. 

  • To stick fast or cleave, as a glutinous substance does; to become joined or united. 

cohere

verb
  • To be consistent as part of a group, or by common purpose. 

  • To stick together physically, by adhesion. 

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