Provided always, and be it further enacted, That if any Person or Persons to whom any such Certificate as aforesaid shall be granted, (hall neglect to pay into the Bank the Consideration Money therein to be specified, for the Space of Thirty-one Days after the Date of such Certificate, or shall neglect to enrol such Certificate and the said Cashier's Receipt for the Money, for the Space of Two Calendar Months after the Date of such Certificate, then every such Certificate shall be null and void, and the Consideration Money, if paid into the Bank, shall be forfeited, unless the Commissioners of His Majesty's Woods, Forests, and Land Revenues for the Time being shall, for any reasonable Cause to be (hewn to them for the Omission of such Enrolment, order the same Certificate and Receipt to be enrolled nunc pro tunc, and which, upon such Cause being shewn, they are hereby authorized and empowered to do.