Full Details

Name and Model Number Russian Circular Slide Rule Evrika
Country of Origin Soviet Union
Date of Manufacture c. 1930
Front Scales D, D, L, K, D, D, A, T, °, S, °
Back Scales None
Scale Length  
Type of Rule Disc
Construction Celluloid cursor and disc of diameter 10 cm mounted on plywood base
Area of Use Generic
Comment Designed and evidently also produced by engineer M. G. Braverman. Hand written number 71 on the cardboard case is probably the serial number. The slide rule was also sold without a cursor and that explains the redundancy of scales. A model with 15 cm diameter was also available. Evrika means eureka in English.
Rarity RRR
Donor Collection of Timo Leipälä
Match Number 361
(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.