Full Details

Name and Model Number Courvoisier
Cercle a Calculs
Country of Origin France
Date of Manufacture c. 1945
Front Scales Spiral scale in 20 revolutions
Back Scales NONE
Scale Length 8-m
Type of Rule Slide Rule
Construction Enamled aluminum plate (24-cm dia.) with celluloid cursors. Fixture on one cursor helps find the correct winding for results.
Area of Use Generic
Comment Compound cursor aids in determining on which revolution of spiral scale the result is found.
Rarity RRR
Donor Collection of Ed Chamberlain
Match Number 115
(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.