(1)  Save as otherwise provided in section 66, the service of any notice under this Act shall be made by delivering or tendering a copy thereof signed, in the case of a notice, by the officer therein mentioned, and, in the case of any other notice, by order of the Collector.

   (2)  Whenever it may be practicable, the service of the notice shall be made on the person therein named.

   (3)  When such person cannot be found, the service may be made on any adult member of his family residing with him; and, if no such adult member can be found, the notice may be served by fixing the copy on the outer door of the house in which the person therein named ordinarily dwells or carries on business, or by fixing a copy thereof in some conspicuous place in the office of the officer aforesaid or of the Collector or in the court-house, and also in some conspicuous part of the land to be acquired:

   Provided that, if the Collector or Judge shall so direct, a notice may be sent by post, in a letter addressed to the person named therein at his last known residence, address or place of business and also publish the same in at least two national daily newspapers and also on his website.