Without prejudice to any powers, whether statutory or otherwise, already enjoyed by an heir of entail in possession of an entailed estate in Scotland to grant feus of any part of such estate, any such heir in possession may, notwithstanding any prohibition or limitation in the deed of entail, or in any Act of Parliament, grant feus of any part or parts of such estate, and that for such feu-duty as such heir shall think fit; but excepting from the provisions of this section the mansion house, offices, garden, orchards, and policies or enclosures adjacent to or in connexion with the mansion house, in so far as such offices, garden, orchards, policies, or enclosures are necessary to the amenity of the mansion house :
Provided that it shall not be lawful for such heir of entail in possession in virtue of the provisions of this section—
(a)to grant any feu unless the nearest heir of entail, being of lawful age and subject to no legal incapacity, shall consent thereto and shall sign the feu-charter, feu-contract, or other deed constituting the feu in token of such consent, or unless in the event of such nearest heir refusing or withholding such consent or signature, or in the event of the nearest heir not being of full age or being subject to any legal incapacity, the sheriff of the county within which the entailed estate or the part thereof proposed to be feued is situated, upon the application of such heir of entail in possession duly intimated to such nearest heir (who shall be entitled to appear and object), shall have found that the granting of such feu is in accordance with the provisions of this section, and that the feu-duty is in all the circumstances fair and reasonable ; or
(b)to feu more than ten acres of land to or for behoof of the same person; or
(c)to take any grassum or valuable consideration other than the feu-duty for granting any such feu.