| Name and Model Number | Ricoh 159 |
| Country of Origin | Japan |
| Date of Manufacture | 1965 |
| Front Scales | LL/1 LL/2 LL/3 A [ B BI K CI C ] D LL3 LL2 LL1 |
| Back Scales | Sh1 Sh2 P2 P1 [Q Sr sθ Th C ] D T2 T1 |
| Scale Length | 25 cm |
| Type of Rule | Slide Rule |
| Construction | Body – celluloid on bamboo, cursor – plastic |
| Area of Use | Electrical |
| Comment | Considered to be one of the rarest hyperbolic slide rules by William K Robinson ( http://ww2.hyperbolicsliderules.com:8110 ). |
| Rarity | RRR |
| Donor | Photo courtesy of Jodie Hobson |
| Match Number | 385 |
| 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. |