The county surveyor, or some person appointed by the court to survey, shall in all cases attend the processioners or the persons selected by the parties. He shall make out a plat and certificate of the land of the applicants, noting what is done, and his plat and certificate shall be returned with, and be considered a part of, the processioners' report. The processioners and surveyor, in establishing lines and corners, may make proper allowance for the variation of the needle.