Full Details

Name and Model Number Baines slide rule No. 1
Country of Origin United Kingdom
Date of Manufacture Patented 1903
Front Scales Velocity, Loss of head, Pipe diameter, Discharge in GPM, Discharge in CuFt/Sec
Back Scales  
Scale Length 23.5 cm
Type of Rule Slide Rule
Construction Four wooden members kept aligned by a brass pantograph on the back
Area of Use Other
Comment An unusual device that uses the pantograph linkage to keep the four scales at equal separation.
Used for hydrological calculations using Flamant's formula.
Rarity RRR
Donor Collection of Nathan Zeldes
Match Number 410
(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.