| 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 |
| Thumbnail (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. |