09-043. Swiss, 2nd quarter 20th century, signed on the ends of the stand "LOGA." Paper-faced aluminum cylinder, 2 1/2" diameter x 12 3/4" long, with sliding grid cylinder, 6 5/8" long, mounted on a metal stand, 14 1/8" long x 4 3/8" deep, and standing 3 3/4" high overall. There are 20 scales, 9 3/4" long each, on the inner cylinder (for a total length of 195 inches) and the same number, 5 1/4" long each, on the sliding grid. The calculator is in very good overall condition, with no damage to any scale. While the large Rechen-Walze sysyem calculators by Nestler, Loga, etc. are not rare, this extremely small model is quite rare and is highly prized by European slide rule collectors. This "super" slide rule appears to combine features of Major General Hannyngton's linear grid slide rule and Thacher's cylindrical calculator. It differs from the former in that there is no numerical overlap of the base scales on the inner cylinder and from the latter in that each grid bar contains only one scale and the grid bar scales are half the length of the base scales.