And be it enacted, That when the said Lords Commissioners of His Majesty's Treasury or any Three of them shall, in any such Case as herein-before mentioned, have substituted, in Writing under their Hands and Seals, a Declaration in lieu of an Oath, solemn Affirmation, or Affidavit, such Lords Commissioners shall, so soon as conveniently may be, cause a Copy of the Instrument substituting such Declaration to be inserted and published in the London Gazette; and from and after the Expiration of Twenty-one Days next following the Day of the Date of the Gazette wherein the Copy of such Instrument shall have been published, the Provisions of this Act shall extend and apply to each and every Case specified in such Instrument, as well and in the same Manner as if the same were specified and named in this Act.