“ On every such trial the jury sworn to try the issue may give a general verdict of guilty or not guilty upon the whole matter put in issue upon such indictment or information, and shall not be required or directed by the court or judge before whom such indictment or information shall be tried to find the defendant or defendants guilty merely on the proof of the publication by such defendant or defendants of the paper charged to be a libel, and of the sense ascribed to the same in such indictment or information. ”