Fowler's Type RX Long Scale Calculator

Country of manufacture: England,            Date of manufacture: ____
Diameter: 6.6 cm,      Thickness: 1.3 cm,      Weight: 111.0 gms
Materials: metal, glass
Scales: 12,
Front: C-short, C-long (5 turns)
Back: C-short, CI, L, A (2 turns), S
Gauge Marks: [Loge10 (2303), π, π/4 (7854) ]
Condition: C7 (Minimal signs of use but on front side, there is a crack on the internal hairline glass plate. Depending on which direction it is being rotated, the two pieces can separate slightly and affect accuracy of readings.)
Came with: Silk pouch and wooden case