Mode of signifying communications from the Railway Board.

    Any notice, determination, direction, requisition, appointment, expression of opinion, approval or sanction, to be given or signified on the part of the Railway Board. for any of the purposes of, or in relation to, any powers or functions with which it may be invested by notification under section 2, shall be sufficient and binding if in writing signed by the Secretary to the Railway Board, or by any other person authorized by the said Railway Board to act in its behalf in respect of the matters to which such authorisation may relate; and the said Railway Board shall not in any case be bound in respect of any of the matters aforesaid unless by some writing signed in manner aforesaid.