Fearns Circular Slide Rule

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Country of manufacture: England,            Date of manufacture: ____,
Diameter: 12.8 cm,      Weight: 69.0 gms
Materals: plastic; simplex form
Cursor: plastic, one line on front.
Scales: 8
Front: K, C [ D, B ] A, Log-Log (spiral), S, T
Back: Conversion Factors, Weights of materials, Weights of Metals
Gauge Marks: [ π]
Condition: C0-C1 (Mint with all extras; some may not be in mint condition)
Came with: Original black plastic case w/snap closure embossed "Industrial Scientific Instruments Ltd., P. O. Box 33, Rouses Point, New York", Instruction leaflet

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