Section 16. At any time before the expiration of thirty days from the entry of a judgment in a case, any party aggrieved by such judgment who files an affidavit in court that he has not received notice of the proceedings by registered mail and that any signature of his appearing on any receipt for registered mail filed with the papers in the case is neither his signature nor signed by one having authority so to do, and that in no other way did he receive actual notice, or have knowledge, of the pendency of the proceedings within the time allowed for filing an appearance and answer, may appeal from said judgment for a jury trial on any question of fact. Within said thirty days after such judgment, issues shall be framed in the land court and the case entered in the superior court for trial as provided in section fifteen.