| Name and Model Number | Wilson's Cylindrical Calculator for Rule Work |
| Country of Origin | USA |
| Date of Manufacture | c. October 1915 |
| Front Scales | Paper cylinders with font sizes |
| Back Scales | None |
| Scale Length | 20 cm (8 inches) |
| Type of Rule | Cylinder |
| Construction | Wood case with glass cover, paper cylinders |
| Area of Use | Generic |
| Comment | "Wilson's Cylindrical Calculator for Rule Work" was probably used in the printing industry to help with spacing and layout. |
| Rarity | RRR |
| Donor | Collection of Lou Gotlib |
| Match Number | 302 |
| 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. |