Notwithstanding anything contained in the provisions of Part III of the Act of 1863, the interest on all debenture stock and on all mortgages at any time after the passing of this Act created and issued or granted by the Company under this or any subsequent Act shall, subject to the provisions of any subsequent Act, rank pari passu (without respect to the dates of the securities or of the Acts of Parliament or resolutions by which the stock and mortgages were authorised) and shall have priority over all principal monies secured by such mortgages. Notice of the effect of this enactment shall be endorsed on all mortgages and certificates of debenture stock issued after the passing of this Act.