Full Details

Name and Model Number Keuffel & Esser 4132
Crane Sewer Rule
Country of Origin USA
Date of Manufacture 1921
Front Scales Egg-Shaped: Cu Ft per second [ Coefficient -- Parts Full ; Slope per 1000 -- Horizontal diameter ] Acres -- slope per 100
Back Scales Circular: Cu Ft per second [ Parts full ; diameter ] slope per 100
Scale Length n/a
Type of Rule Slide Rule
Construction Boxwood
Area of Use Other
Comment Special slide rule for use by sewer engineers in designing sewer systems.
For sewer drainage and flow calculations.
Rarity RR
Donor Collection of Dr. Paul J. Tarantolo Jr.
Match Number 36
(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.