Graphic pH Calculator Slide Rule

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Country of manufacture: USA,            Date of manufacture: >= 1958
Overall length: 28.4 cm,          Width: 5.6 cm.,           Weight: 47.3 gms
Materials: all plastic, closed form simplex.
Cursor: no cursor
Scales: specialized
Front: A (Acid) [ B (Base), C (pK) ] D (pH)
Back: Instructions for use.
Well, Back, and Slide Back: Blank
Condition: C3 (Signs of Very Minimal Use)
Came with: Paper sleeve, leather sheath, article from Science magazine

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Slide Back

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