In all cases where any lands or hereditaments are charged with any F1fee-farm rent, rent seck, rent of assize, or chief rent, or other annual or periodical fixed rent, or other certain payment, any persons respectively interested, according to the provisions of the said Acts, in such lands, and in the said rent or other certain payment as aforesaid issuing therefrom, may make application in writing to the said commissioners to apportion the said rent or other fixed payment among all the lands charged with the payment thereof, and the commissioners, upon receipt of such application, shall, by themselves, or by an assistant commissioner or other person to be by them appointed for think fit; purpose, make inquiry, and satisfy themselves as to the expediency of such apportionment: Provided always, that if in any case there shall be any doubt as to the extent, identity, or boundaries of the lands and hereditaments charged with any such rent or payment, the commissioners, assistant commissioner, or other person appointed by them as aforesaid shall inquire into and ascertain such extent, identity, or boundaries.

F2No application for apportionment shall be made under this section in a case in which an application for apportionment may be entertained under the M1Rentcharges Act 1977.