Any form, other than a record of order or direction which is required by these rules to be signed by the Authority may be signed under his direction and on his behalf by any officer sub—ordinate to him appointed by him in writing for this purpose.
' ll. Exercise of powers t—In exercising the powers of Civil Court conferred by section 18 the Authority shall be guided in respect of procedure by the relevant orders of the First Schedule of the Court of Civil Procedure, 1908, with such alternations as the Authority may find necessary, not affecting their substance, for adopting them to the matter before him, and save where they conflict with the express provisions of the Act or these rules.