Thornton PIC No. 121 Differential Electro

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Country of manufacture: England,            Date of manufacture: ____
Overall length: 30.6 cm,          Width: 4.5 cm,           Weight: 130.4 gms
Materials: Closed form simplex; celluloid lamimate over mahogany, pinned
Cursor: 4.0 X 3.9 X 0.6 cms; metal framed glass;  lines: one
Scales: 14
Front: 27 cm // E₁ (unlabeled), E₂ (unlabeled), int + A [ B, CI (unlabeled), ISd-ITd, Td-Sd, C ] d + D, K (unlabeled) \\ 10 in
Well: Manufacturer & Model Number ID.; otherwise blank
Slide Back: blank
Back: decimal-inch equivalents, mathematical constants, conversion factors, physical constants, weights and strengths of materials
Gauge Marks: [ π, C (1129), " (2063), L (2303), M, (3183), m (3438), C1 (3568), U (5729) ]
Condition: C5 (Signs of Normal use)
Came with: Original dark green cardboard box/case

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