In all Cases where the Enrolment of any Deed or other Instrument in the Office of the Duchy of Cornwall has been or shall be omitted or delayed beyond the Period provided for the Enrolment thereof, either by this Act or otherwise, it shall be lawful for the Duke of Cornwall, or any Person whom the Duke of Cornwall shall by Sign Manual Warrant appoint to act in that Behalf, or, in the Absence of such Appointment, for the Keeper for the Time being of the Records of the Duchy of Cornwall, upon reasonable Cause being shown for the Omission or Delay, to direct or permit the making of any such Enrolment nunc pro tunc, and every such Enrolment when made shall be as valid and effectual as if made within the Period limited for that Purpose either by this Act or otherwise.