Section 69. In the district courts in actions not governed by the District-Municipal Courts Rules of Civil Procedure, a party by written demand filed in the clerk's office and notice given by copy thereof by registered mail, return receipt requested, to the other party or his attorney, not less than ten days before the trial of the action or suit, may call upon the other party to admit, for the purposes of the case only, any material fact or facts or the execution of any material paper or document which the party filing the demand intends to use at the trial. Copies of the papers or documents shall be delivered with the demand unless copies have already been furnished. An affidavit of such notice and the return receipt, if any, shall forthwith be filed in the clerk's office. The court may delay the trial until such demand is answered and on motion before trial may strike out of such demand or any answer filed in response thereto any matter which is irrelevant, immaterial or improperly included therein. After the filing of said affidavit of notice, each of the matters of which an admission is demanded shall be deemed admitted unless within ten days after mailing the demand, or within such further time as the court may allow on motion and notice, the party to whom the demand is directed files in the clerk's office a sworn statement either denying specifically the matters of which an admission is demanded or setting forth in detail the reasons why he cannot truthfully either admit or deny those matters. Any admission made by a party by answering or not answering such demand is for the purpose of the pending proceeding only and neither constitutes an admission by him for any other purpose nor may be used against him in any other proceeding, but said admission shall be binding upon him in the pending proceeding unless he is relieved therefrom by the court for cause shown. If the party upon whom such demand is made refuses to admit any fact or the execution of any paper or document mentioned in the demand, the reasonable expense of proving such fact or the execution of such paper or document, as determined after summary hearing by the justice presiding at the trial, shall, unless the justice certifies that the refusal to admit was reasonable, be paid by said party to the other party and the amount thereof shall be added to the taxable costs of the party in whose favor such amount is awarded or deducted from the amount of any judgment or decree against him.