The person for the time being entitled to, and in the enjoyment of, the title of Baronet conferred by the said Letters Patent as aforesaid, shall have power with a view to the more advantageous sale of the land occupied by the said Mansion House and other hereditaments, called Mazagon Castle, in other hereditaments, called Mazagon Castle, in pursuance of the powers in that behalf conferred by section 10, and, notwithstanding anything in this Act contained to the contrary, to enter into an arrangement with the Government of Bombay whereby, in consideration of the waiver in perpetuity by the Government of Bombay of their right to enhance the amount of the assessment to land revenue for the time being payable in respect of the land occupied by the said Mansion House and other hereditaments, called Mazagon Castle, either the amount of the assessment to land-revenue payable in respect of any land which may be purchased in pursuance of the power in that behalf conferred by section 8, may be enhanced, or an assessment to land-revenue of any land so purchased, which at the time of the purchase thereof shall not be liable to the payment of land-revenue, may be imposed thereon.