(g) the discharge of any mortgage so registered on the certificate may be endorsed on the certificate by the Registrar of Ships or proper officer on the production of such evidence as is, by this Act required to be produced to the Registrar of Ships for the entry of the discharge of a mortgage in the register book; and, on that endorsement being made the interest, if any, which passed to the mortgagee shall vest in the same person or persons in whom it would, having regard to the intervening acts and circumstances, if any, have vested if the mortgage had not been made;