Full Details

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
(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.