Ratcliffe Spring Calculating Slide Rule

---

Country of manufacture: England,            Date of manufacture: ____
Overall length: 30.0 cm,          Width: 6.9 cm,           Weight: 149.0 gms
Materials: celluloid covered printed papers scales laminated onto wood
Cursor: 5.0 X 8.0 X 0.6 cms; plastic runners and lens, front side only; lines = one line plus spring index scale
Scales: 9, specialized
Front: D [ d, dc, w ] f, DI [ di, R ] N
Back: Instructions for Use
Upper Well: Instructions continued;    Lower Well: English equivalents of Metric wire spring diameters
Condition: C2-C3 (Mint to very minimal signs of use; no manual)
Came with: Original cardboard box/case

---

---