Full Details

Name and Model Number Illgen Rechentafel
Country of Origin Germany
Date of Manufacture c.1910
Front Scales 10 sections repeated 4x horizontal and vertical
Back Scales none
Scale Length 2-m
Type of Rule Data Chart
Construction Enameled metal 35-cm x 21-cm; with transparent slide
Area of Use Generic
Comment Gridiron table form of slide rule; early example without maker's name.
Maker identified from hand written note in pocket
on the reverse with help of Stephan Weiss.
Rarity RRR
Donor Collection of Ed Chamberlain
Match Number 101
(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.