The Sheppard slide rule was patented by F. H. Sheppard in 1878 and designed to calculate area and volume in either feet and inches, or in decimal feet. The scale layout at first appears very simple: three pairs of what we would now call A and B scales: 2-cycle logarithmic scales. However, the left side of each scale is divided duodecimally (into 12ths) and the right side is conventionally divided into 10ths. The Sheppard is effectively two slide rules mounted on top o...f each other, with the top slide rule solving for area, and the bottom slide rule using the result of that calculation as the starting point for calculating volume. No cursor was provided and none is needed as all calculations are between adjacent scales. Problems of volume are solved top to bottom, multiplying length times breadth times thickness, and reading the answer on the bottom scale. There are no markings on the backs of the slides, under the slides, or on the back of the slide rule body. W. F. Stanley carried the Sheppard “Cubing Slide Rule” in their catalog until at least 1930, and described it as, “Cubing Slide Rule, Shepard’s, with two slides, giving at sight square or cubic contents in feet and inches up to 100 cubic feet, specially designed for quantity surveyors, timber merchants, etc., with instructions for use.” It was available in both 12-inch and 22-inch versions. This is the 12-inch version, which actually measures 13.25 inches long. The slide rule is quite thick, 0.45”, and the body is made from a single piece of boxwood rather than a back plate with separate pieces for the stators glued down. There are numbers stamped on one end, presumably for keeping the body and stators for each individual slide rule together during production. This slide rule is in magnificent condition, and age has given the boxwood a beautiful color. The only flaw, and it really is insignificant, is a few tiny ink stains on the upper edge, probably from someone using the slide rule as a straight edge when drawing a line with a fountain pen. This slide rule is from the collection of Robert K. (“Bob”) Otnes, PhD, one of the founding members of the Oughtred Society and the original editor of the Journal of the Oughtred Society. It is being sold by the Oughtred Society on his behalf. The Oughtred Society was founded in 1991 by a group of slide rule collectors and is dedicated to the preservation and history of slide rules and other calculating instruments. Membership is open to anyone. Further information about the Oughtred Society can be found at: http://www.oughtred.org/. PayPal is the only accepted form of payment. Buyers within California will be charged 7.25% sales tax. Shipping will be by USPS Priority Mail. Shipping charges will be somewhat higher for destinations outside the USA.