(4)A summons may, if the Revenue Officer or Revenue Court so directs be served on the persons named therein, either in addition to, or in substitution for, any other mode of service, by forwarding the summons by post in a letter addressed to the person and registered under Part III of the [Indian Post Office Act, 1866. (XIV of 1866).] [See now the Indian Post Office Act, 1898 (6 of 1898).]
