Full Details

Name and Model Number Otis King Calculator
Model M
Carbic Ltd.
Country of Origin England, London
Date of Manufacture 1923
Front Scales Scale No. 418: Numbers 0.0025-100000 (logarithmic)
Back Scales Scale No. 419: Numbers 1-10000 (logarithmic)
Scale Length 25 cm
Type of Rule Cylinder
Construction Nickel plated brass with paper scales. Scales printed in spiral fashion around the upper cylinder and lower handle.
Area of Use Generic
Rarity RRR
Donor Collection of Dr. Paul J. Tarantolo Jr.
Match Number 216
(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.