Full Details

Name and Model Number Vade Mecum
Timber Slide Rule
Country of Origin England
Date of Manufacture c. 1900
Front Scales A [ B C ] D, /measuring scales 1/8", 1/4", 3/8"
Back Scales E F [ G G/ H1 H2 H3 I ] J K
Scale Length 11.2"
Type of Rule Slide Rule
Construction Boxwood with brass end braces
Area of Use Other
Comment For calculating the volume of timber in logs.
Designed by George Bousfield for the timber trade.
Designed to be held vertically when used.
Rarity RRR
Donor Collection of Clay Castleberry
Match Number 244
(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.