¶1It is not a conclusive, but only a prima facie presumption, which may be repelled by proof of payment of some part of the debt, or a written acknowledgment of a right of action within twenty years. (§ 48.) The statute has not altered the form of pleading. The plea should be payment, upon which issue should be joined. Under that .issue the defendant may show actual payment, or rely on the lapse of time as a ground for presuming payment. And in answer to the presumption, the plaintiff may show a partial payment, or a written acknowledgment of a right of action within twenty years.
¶2If the defendant cannot, with a good conscience, make an *315affidavit of the truth of the plea in the words of the 99th rule, he may swear to the facts which show the plea to be true, to wit, that the judgment was recovered more than twenty years before the commencement of the suit, and that he has made no payment, nor given any written acknowledgment of a right of action on the judgment, within twenty years.
¶3Judgment for the plaintiff.