Section 15. Power to alter rent when holding is increased, diminished or deteriorated.

When the area of a holding the rent of which is payable in money is increased or diminished by the encroachment of the tenant or the landlord, or by, fluvial action or otherwise, or the soil of a holding is, without the fault of the tenant, permanently deteriorated by a deposit of sand or by any other calamity, a Revenue-officer may, notwithstanding anything in the record-of-rights or any contract between the parties, by order, on the application of the landlord or of the tenant, alter the rent with reference to that increase, diminution or deterioration.