(1) An indorsement in blank specifies no indorsee, and a bill so indorsed becomes payable to bearer.
(2) A special indorsement specifies the person to whom, or to whose order, the bill is to be payable.
(3) The provisions of this Act relating to a payee apply with the necessary modifications to an indorsee under a special indorsement.
(4) When a bill has been indorsed in blank, any holder may convert the blank indorsement into a special indorsement by writing above the indorser's signature a direction to pay the bill to or to the order of himself or some other person.