Full Details

Name and Model Number Lord's Calculator 1
by R. Waddington
Country of Origin England (Coventry)
Date of Manufacture unknown
Front Scales D [ C, B ] A -- W
Back Scales none
Scale Length 6.5"
Type of Rule Watch Type
Construction Metal case with glass front, solid back, and fixed (D A) and moveable (C B) metal scales. Main stem turns outer moveable scale C. Side stem turns inner moveable scale B.
Area of Use Other
Comment Basic mathematical and textile calculations.
Fixed Inner Scale: A scale - Reeds and Picks from 120 to 30, W scale - Percentages 0 to +60 and 0 to -30.
Rarity RR
Donor Collection of Dr. Paul J. Tarantolo Jr.
Match Number 56
(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.