| Name and Model Number | Hemmi No. 31 Pocket Rule With Decimal Keeping Cursor |
| Country of Origin | Japan |
| Date of Manufacture | c. 1930s |
| Front Scales | A [B C] D |
| Back Scales | S L T |
| Scale Length | 10 cm |
| Type of Rule | Slide Rule |
| Construction | Celluloid on bamboo |
| Area of Use | Generic |
| Comment | Special decimal indicating cursor.
Thin metal back holding stators in place and providing control of slide friction. Back is pierced with the "SUN" logo flanked by sun bursts. Decimal keeping mnemonics on top and bottom stators. |
| Rarity | RRR |
| Donor | Collection of Ed Chamberlain |
| Match Number | 126 |
| 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. |