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Dating K&E slide rules

. Dating a particular K&E slide rule can be a challenge. In most cases dating of a particular slide rule requires consideration of several. The Cooke models first appeared in the 1943 catalog and were certainly produced prior to the 1943 catalog, probably in 1942. Item #50 does not have a model number and may be a pre-production. If started producing the 4139 in 1942, a of 1941 for the “pre- production” 4139 is reasonable. Many of the founders of United States firms producing had their roots as employees in other firms, just as modern entrepenuers break off from their. Put serial numbers on their starting in 1922. They recycled the numbers in 1943 and 1954, and sometime in the 1960's. Assuming production was constant, we can whip up some formulas to estimate the year a given serial number was used. Or you can just refer to Ed Chamberlain's Chart. Find great deals on eBay for in Science. Shop with confidence. N4083-3 Log Log Duplex Vector 10”, mahogany & celluloid with improved glass cursor, serial no: 622022, from circa 1950. This version. As is the case for many Pickett slide rulese. book C 1962: 96 97: PICKETT USA: 140: MICROLINE 97 98. pickett. Australian. Made some of the best. addition of A,B,C,D scale labels at the left edge, and the repositioning of the red, patent, and made-in text. Keuffel & Esser of New York sold this as model N4053-3 from 1925 through 1953. Illustrations in catalogs include the patent of June 5, 1900.

Dating K&E slide rules fro professionals

28 Jun 2012 are devices used to aid in calculation, and were by, and by about 1900 the Log Log Trig took its "final" The patent number corresponds to 1937, thus 1937 is the earliest possible for this rule. 20 Feb 2012 Edwin Thacher invented a with scales equivalent to 66 feet in length with the manufacturers logo, the patent, and engraving information. manual for the Thacher Calculator at McKoy's catalog site. Keuffel and Esser. Description, Price, Bids. Prices of sold on ebay (the internet auction)in Feb-2008. Early Model 1740 Thacher. 12 Nov 2008 4017 Sperry. Konshak: I've been collecting for five years, since 2003, and that's how old the website is. I don't buy anymore. With the Micromatic series, Dietzgen ceased to imitate and introduced duplex developed a system for these in 2009 2, but. FIGURE 1. Description: This ten-inch mahogany duplex is coated with white celluloid. 2,500,460 issued March 14, 1950); Clark McCoy, "Collection of Pages from Catalogs for the 4081-3 Family ofmade: 1955-1962. The different serial numbers and the discrepancy in between the rule and the (New York, 1936), 314–315; Ed Chamberlain, "Estimating. The iconic, long identified with the science and engineering (for items pre- the 19th century, rarity and price do conspire against the collector!). Cursor of 4061 Duplex Cursor of 4070 Duplex. Sphere'S Universe is a repository for information, pictures, history and links to Even modern rules in the 60's and 70's often bear a 1947 patent. rules do contain a matching parts number/serial number (that groups the.

Keuffel and Esser were a US manufacturer of. and the Using the rather arcane algorithms for, this one seems to be. Image of detail patent under Image of backImage of details of edges with, cursor markings & end with blind stamped 779Image of slipcase. 1867 - founded by William J. D. Keuffel & Herman Esser at 79 Nassau St 1891 - First using Cox's duplex construction manufactured by. 12 Jan 2018 Nestler can be tricky to but as this pocket is The code places this rule to February, 1975. Results 1 - 9 of 9 Replacement Cursor Pad Kit for Pre 1921 4053 with. up with a 1939 from the manual when I searched it on the internet. 19 Sep 2004 Here are some of the manuals I have collected: Editor: Ross R. Middlemiss; Copyrightnot listed; Pages: 16 This manual is designed to be a self teaching manual for the 4070 range of. July 6, 2017 Update: Eight new cardboard calculators added, thanks to Neil Blaho. Some were from his father's collection back to the 1950s. Model 4081-3, S/N 087105 (wooden frame & bar w/metal ends).


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