Indian Post Office Act, 1898
(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.