If the grantor and witness or witnesses of any instrument of writing be dead or absent, so that the personal attendance of neither can be had, it may be established by the oath of any person who, on examination before an officer competent to take acknowledgments, can prove the handwriting of the deceased or absent witness or witnesses; or when such proof cannot be had, then the handwriting of the grantor may be proved, and the officer before whom such proof is made shall certify accordingly, and such certificate shall be deemed equivalent to an acknowledgment by the grantor or proof by a subscribing witness, and entitle the instrument to be recorded.