Scope and ContentThe Mannheim Slide Rule; Nos. 4031S, N4035S, N4041 and 4051. A Self Teaching Manual with tables of settings, equivalents and guage points by William E. Breckenridge. Published by Keuffel & Esser Co., New York & Hoboken, N.J., [copyright 1938], not issued after 1939 (L.A. branch not listed on cover and title page.) Booklet, 5-5/16" x 7-7/8" high, pp [ii], 75, [2]. Dampstain lower half. Copyright date and issue date are not necessarily the same. Back cover code: 43343.