Full Details

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.
Rarity RRRR
Donor Collection of Mike Frey
Match Number 269
(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.