Series consists of 39 letterpress copy books; copies of correspondence written out of the Chicago office. Earlier volumes are president's reports to chairman of Executive Committee, later from vice-president in Chicago to treasurer and president. Reports consider weather, business, cars loaded and received, local treasurer's report, land sales, etc.; after 1877 more detailed reports on forms, including cumulated reports at end of month and year, A few letters are included in some volumes. No reports for Nov. 1881-Apr. 1882, July 1889-Mar. 1890, Feb.-Dec. 1899 and Oct. 1895-June 1896.