Full Details

Name and Model Number L. Appoullot
Country of Origin France
Date of Manufacture  
Front Scales C, L, sqr root, cube root, sqr root, cube root, cube root, S1, T1, S2, T2
Back Scales None
Scale Length 19.7 cm diameter
Type of Rule Disc
Construction Tin
Area of Use Generic
Rarity RRR
Donor Collection of Rod Lovett
Match Number 2

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.