|Name and Model Number||Keuffel and Esser 1744B |
Wm. Cox Patent 1891
|Country of Origin||USA|
|Date of Manufacture||1897|
|Front Scales||With Slide 1: A [ B C ] D, With Slide 2: A [ BI CI ] D|
|Back Scales||With Slide 1: A [ B C ] D, With Slide 2: A [ S L T ] D|
|Scale Length||25 cm|
|Type of Rule||Slide Rule|
|Construction||Celluloid on mahogany, engine divided scales, brass chisel cursor|
|Area of Use||Generic|
|Comment||Brass chisel cursor. Brass end plates wrap around ends of rule.
Front lower stator is inscribed: Wm. COX PAT. OCT. 6, 1891.
Back lower stator is inscribed: KEUFFEL & ESSER Co., NEW-YORK.
|Donor||Collection of Mike Frey|
(Click Picture for Details)
|In conjunction with our 'donors' we assign a rarity rating to each item, based on the system devised by Herman van Herwijnen|
|(1929 - 2004), renowned Dutch collector, author, and creator of Herman's Archive, a collection of 5,000 slide rule images on CD.|
|• RR = Rare - 1 of 25 collectors has one; it may take a year to find an example in the marketplace.|
|• RRR = Very Rare - only a few known to collectors; may be several years before it comes up for sale.|
|• RRRR = Extremely Rare - a museum piece; unlikely that an example will come up for sale.|