BRL Vector Slide Rule

---

Country of manufacture: England,            Date of manufacture: ____
Overall length: 38.2 cm,          Width: 21.5 cm,           Thickness: 1.2 cm           Weight: _____ gms.
Materials: Metal and plastic.
Cursor: 3.5 X 17.0 X 0.6 cm; metal framed plastic lens; top part unframed and unsupported.
Scales: 10
Frame: A (reciprocal. 3-decade log), B (3-decade log), C (3-decade log), D (reciprocal. 3-decade log), E (3-decade log), I (1½-decade log; i.e., gives square root of scales B, C, and E)
Back: blank
Upper Template Slide: Two marking lines 1-decade apart (ref. to scales A-G) and aligned with left- and right-hand bases of upper contour template, upper contour template
Lower Template Slide: Two marking lines 1-decade apart (ref. to scales A-G) and aligned with left- and right-hand bases of lower contour template, lower contour template
Ordinary Slide: F (3-decade log), G (reciprocal. 3-decade log), H (1½-decade log)
Cursor: Bottom part - normal 1-line cursor to be used with scales C to I. Top Part - contains a linear φ-scale divided between 0° and 90° with negative angles in red
Gauge Marks: [ π ]
Condition: C3-C4 (Very minimal to minimal signs of use)
Came with: Instruction booklet

---

---