law: Indian Evidence Act, 1872 
  22. When oral admissions as to contents of documents are
  
  relevant
  Oral admissions as to
  
  the contents of a documents are not relevant, unless and until the party
  
  proposing to prove them shows that he is entitled to give secondary evidence of
  
  the contents of such document under the rules herein after contained, or unless
  
  the geniuses of a document produced is in question.