Name Keuffel & Esser < 4053 - 2 > Polyphase Mannheim Adjustable, dated 1915 and 1921
Front Scales 8inch / A = B CI C = D ] K
Back Scales = S L T =
Type of Rule slide rule
Material Engine divided celluloid laminated mahogany
Dimension (mm)  
Area of Use generic
Origin of Rule Michael O'Leary
Match Number 4102
Comment  
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