| Name and Model Number | Keuffel & Esser Co. Calculigraphe Model 4022 |
| Country of Origin | France |
| Date of Manufacture | c. 1905 |
| Front Scales | L, 3 rev. spiral C scale, also functions as cube root scale. |
| Back Scales | Sine, C, K |
| Scale Length | 3 rev. C scale is 30-cm long |
| Type of Rule | Watch Type |
| Construction | Scales on paper, 5.25-cm dia. housing case is metal & glass |
| Area of Use | Generic |
| Comment | This Calculigraphe was probably made in France and resold by K&E. There are no K&E markings on this example. The rare detail is that it came with K&E Instructions. According to Peter Hopp, the expert on pocket watch slide rules, these instructions are unique. |
| Rarity | RRRR |
| Donor | Collection of Ed Chamberlain |
| Match Number | 120 |
| 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. |