K e slide rule dating
Lacking: original instruction booklet, box or case.
Missing clear plastic (xylonite) window at right edge. Engraved at center front with company name, "Keuffel & Esser Co., N. June 5, 1900." This date is not relevant to the manufacture date.
Polyphase (Mannheim type) 10" slide rule, 4053-3, made by Keuffel & Esser Co., New York, copyright 1900, made and issued circa 1915-1922.
Mahogany, machined and laminated, with laminated white celluloid plastic ruled ("engine divided") scales in red and black; bottom edge has laminated scale (sine); top front edge beveled with laminated white celluloid ruler, English measure by inches and sixteenths; 10-5/8" overall length x 1-5/16" high x 3/8" thick.
K&E had their main office and factories in Hoboken when this item was made.
The firm was founded in 1867 by William J D Keuffel and Hermann Esser to sell drawing materials and instruments. The firm and its products grew steadily and they became the leading manufacturer of slide rules in the USA as well as makers and suppliers of a wide range of drawing and surveying instruments.
Slide rules were the primary tool for performing multiplication, division and other scientific functions up through the 1960s and the development of the electronic calculator.
There are straight, circular and cylindrical slide rules, all collectible.
)Overall dimensions: 21-1/2" wide x 5-1/2" deep x 5-3/8" high. Brass frame, 4-3/4" diameter, mounted on open style brackets; internal cloth pads on bars to keep internal cylinder tight and in place plus protect it from wear. Also a printed manufacturer's plate (ivory colored celluloid - Ivorite? patent 249,117.----spiral slide ruleanalog calcula Dating of this object: Online references have stated that K E started making the Thacher in America by 1897 (this seems to infer that any of them prior to that date were made abroad and imported.) This online information does not source this information by citing any authorities. For the names used for scales and gauge points see A-to-Z. I have used the following way of indicating the location of scales.(L), K, A[B, CI, D/ L1, L2, L3] D, P (S, T) where: scales on edge of rule are in round brackets () scales on stock are unbracketed scales on slider are in square brackets : the forward slash (/) indicates scales on both faces of slider. I use small flags to indicate the country of origin.Missing: adjustable magnifier; instruction booklet. The size and number of scale bars made this slide rule function as if it were a 40-60 foot long slide rule (this is not stated by K&E, but a typical statement from slide rule collectors' descriptions of their holdings of this model) and allowed a precison to five decimal places.K E general offices and factory were in Hoboken during the period when this item was made.
scales in the well of the stock are in curly brackets . Where two flags are shown the first represents the origin of the company who marketed the rule and the second the origin of the company who manufactured the rule.