law: Registration Act, 1908
  51. Register books to be kept in the several offices
  (1) The following books shall be kept in the several offices
  
  hereinafter named, namely:-
  (A) In all registration offices-
  Book 1, "Register of non-testamentary
  
  documents relating to immovable property";
  Book 2, "Record
  
  of reasons for refusal to register";
  Book 3, "Register
  
  of wills and authorities to adopt"; and
  Book 4,
  
  "Miscellaneous Register";
  (B) In the offices of Registrar's-
  Book 5, "Register
  
  of deposits of wills".
  (2) In Book 1 shall be entered or filed all documents or
  
  memoranda registered under sections 17,18 and 89 which relate to immovable
  
  property, and are not wills.
  (3) In Book 4 shall be entered all documents registered under
  
  clauses (d) and (f) of section 18 which do not relate to immovable property.
  (4) Nothing in this section shall be deemed to require more than
  
  one set of books where the office of the Registrar has been amalgamated with
  
  the office of a Sub-Registrar.