There shall be no games allowed in the poolroom other than pool, billiards and snooker, and should any other game or games be allowed or conducted in the room, the license herein granted shall be immediately revoked upon notice being served upon the licensee by the board of trustees, and all rights thereunder shall cease, and it is unlawful to continue the business after receipt of this notice. (Ord. dated 9/13/34 § 3).