Full Details

Name and Model Number Mode Frequencies for a Rectangular Plate
Country of Origin England
Date of Manufacture 1972
Front Scales 9 specialised
Back Scales None
Scale Length 35.2 cm
Type of Rule Slide Rule
Construction Cardboard on Wood
Area of Use Generic
Comment The slide rule can be used to set the rough dimensions of a musical instrument soundboard
so that natural frequencies are spaced in a particular way rather than coincident.
Rarity RRRR
Donor Collection of Patrick Barrington
Match Number 87

RR = Rare -- 1 of 25 collectors has one; it may take a year to find an example in the marketplace.   
RRR = Very rare -- only very few known to collectors; may take several years before one comes up for sale.   
RRRR = Extremely rare -- a museum piece; unlikely that an example will ever come up for sale.