The private estates of Her Majesty, her heirs or successors, situate or arising in any part of Her Majesty’s dominions (except Scotland), may be disposed of by Her Majesty, her heirs or successors, in manner provided by the fourth section of the M1Crown Private Estate Act 1800: Provided always, that a will or other testamentary disposition by Her Majesty, her heirs or successors, of or concerning any such private estates as aforesaid, shall not require publication; and every such will or testamentary disposition shall be valid and effectual, if signed by the testator or testatrix, or by some other person in his or her presence, and by his or her direction, in the presence of two witnesses: Provided also, that every will or other testamentary disposition by Her Majesty, her heirs or successors, of any such private estates as aforesaid, made under the authority of this Act and of the M2Crown Private Estate Act 1800, or either of them, and whether made before or after the passing of this Act, shall be construed with reference to the property comprised in such will or testamentary disposition, to speak and take effect as if it had been executed immediately before the death of the testator or testatrix, unless a contrary intention shall appear by the will or other testamentary disposition.