Full Details

Name and Model Number S. Waddington
“The Ich Dien Rule”
Country of Origin England
Date of Manufacture 19th Century?
Front Scales 5 scales, all 2-cycle, some inverted; 6th fixed on middle divider
Back Scales 2 off 12” measuring scales
Scale Length 11”
Type of Rule Slide Rule
Construction Mahogany, brass and ivory
Area of Use Other
Comment Unknown use.
Only one other known, see MHS Oxford 52599
Rarity RRRR
Donor Collection of Peter Hopp
Match Number 35

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.