law: Indian Post Office Act, 1898 
  29. Power to make rules as to registration
  (1) The Central
  
  Government may make rules as to the registration of postal articles.
  (2) In particular and
  
  without prejudice to the generality of the foregoing power, such rules may- 
  (a) declare in what
  
  cases registration shall be required;
  (b) prescribe the
  
  manner in which the fees for registration shall be paid; and
  (c) direct that twice the fee for registration
  
  shall be levied on the delivery of a postal article required to be registered
  
  on which the fee for registration has not been prepaid.
  (3) Postal articles
  
  made over to the Post Office for the purpose of being registered, shall be
  
  delivered, when registered, at such times and in such manner as the Director
  
  General may, by order, from time to time appoint.