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USSR slide ruler, Soviet Measurement tool for engineers and scientists.
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Click to VISIT or RETURN: Buying and Selling Slide Rules To make your life easier, and help you find exactly what you want, we have broken the on-line slide rule catalogs into smaller sections. Vintage logarithmic slide ruler for engineers. Woodworking Ruler, 3Pcs Precision Pocket Ruler Metal Slide Rule Inch and Metric T-Type Scribing Ruler Square Ruler T Track Ruler Marking Measuring Ruler with Slide Stops (6/8/12 Inch) 50. In 1622, William Oughtred created the first slide rule, a simple and easy-to-use calculation device consisting of two parallel logarithmic rulers that can slide past each other. Even more specialized in purpose were slide rules for grading earthworks, determining the effects of nuclear bomb explosions, writing efficient computer programs, and betting on horse races. The Slide Rule Universe All kinds of reference information.
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Other circular slide rules were designed specifically for surveying, such as stadia computers, or for navigation, such as Dalton instruments that may also be seen in the Smithsonian's exhibition, Time and Navigation. Inventors and makers such as Albert Sexton, Louis Ross, Claire Gilson, Norman Albree, and Ross Pickett wanted their circular slide rules to compete with linear instruments in the engineering and education markets. Some circular slide rules were made to look like pocket watches, while others were intended to promote particular businesses-Whitehead & Hoag and Perrygraf were especially influential American manufacturers of promotional items. For example, before Mannheim-type linear slide rules became popular in the late 19th century, American inventors patented a variety of circular designs. This collection suggests the diverse appearances and functions of circular slide rules that were manufactured between the mid-19th and late 20th centuries. However, this simple construction is also not very durable, and so circular slide rules may get out of position and thus they lack accuracy, compared to linear slide rules with slides that move along carefully grooved channels. The slide rule could hardly compete with this, although some of the mentioned features can be fou nd in slide rules. Furthermore, these instruments are relatively easy to construct: the scales are printed on one or more disks, and the disks or a single disk and cursor are fastened together with a pin at the center. The scales are also continuous, so there is no need to make adjustments, such as folded and inverse scales, for results of calculations that go off the ends of the scales. Slide rules that are round offer the length of a 10" rectangular slide rule in a pocket-sized (roughly 3.6") format, since the scales are on the circumference of circles. Eliot Elisofon Photographic Archives, African Art.