And whereas by the first-recited act power is given for altering apportionments of rent-charge by the Commissioners of Land Tax, on the application of the owner of the Lands charged therewith, and it is expedient that the power thereby given should be extended, and also that during the continuance of the Tithe Commission the like power should be vested in the Tithe Commissioners; If at any time after the confirmation of any instrument of apportionment it shall appear that the lands charged with one entire rent-charge belong to or have become vested in several owners, and that any of the owners of such lands shall be desirous that the apportionment thereof should be altered, it shall be lawful for the commissioners of land tax for the county or place where the said lands are situated, or any three of them, to appoint, by notice under their hands, a time and place for hearing the parties to such application, and all other parties interested therein; and upon satisfactory proof of such notice having been served on all parties interested full twenty-one days before the day of hearing, to proceed to alter the apportionment in such manner and in such proportion amongst the said lands as to them shall seem just, subject nevertheless to the consent of two justices of the peace, as in the said first-recited Act provided; and further, that upon such application being made to the said tithe commissioners, they shall have the same power of making such alteration as by the said first-recited Act and by this Act is vested in the commissioners of land tax, and that without any such consent of two justices of the peace; provided that no alteration of any apportionment shall be made under the first-recited Act or this Act whereby any rent-charge shall be subdivided so that any subdivision thereof shall be less than five shillings.