Full Details

Name and Model Number Belcher Brothers
Hatter's Slide Rule
Country of Origin USA, New York
Date of Manufacture 1850-1860
Front Scales Inches to measure the diameter of a hat
Back Scales Table of hat sizes, diameters and circumferences of the hat or head
Scale Length 12 cm (5 in)
Type of Rule Slide Rule
Construction Boxwood and bound grass end pieces brass slide
Area of Use Conversion
Comment Used for the hat trade of the mid 1800s, unusual to have the maker's brand on a hatters slide rule
Rarity RRR
Donor Collection of Clay Castleberry
Match Number 350
(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.