Keuffel & Esser (K&E) 4015 Fuller's Spiral Cylindrical Slide Rule, Model 1, serial number 1948. Composed of an exterior wooden movable cylinder with two brass rings lined with felt over a longer interior wooden cylinder, both covered with paper and marked with decimal, conversion, sine tables, and a logarithmic scale graduated into 7,250 parts, two brass indexes. Housed in a wooden box with ink stamp reading "Calculator". Maker's marks to exterior cylinder. Slide rule – 17" L x 3 1/2" dia. Box – 4" H x 18" W x 4 1/2" D. Early 20th century. (See: https://americanhistory.si.edu/collections/search/object/nmah_694149). Provenance: Private West Tennessee Collection. CONDITION: Toning, areas of surface abrasions to cylinders. Some wear, scratches, natural wood shrinkage to case.