BRL Humidity Slide Rule MK. 6A

Country of manufacture: England,            Date of manufacture: ____
Overall length: 33.7 cm,          Width: 5.0 cm,           Weight: 121.6 gms.
Materials: closed body form, all plastic
Cursor: 3.8 X 5.9 X 1.2 cms; all plastic, slightly magnifying; lines = one on both front and back
Scales: 18, mostly specialized
Front: (4) Vapor Pressure & R.H. % [ (6) Temperature, (5) Pressure, (3) Dry Bulb and Dew Point, (3A) Temperature, (2B) Adjusted Depression of Aspirated Wet Bulb, (2C) Adjusted Depression of Aspirated Ice Bulb, (2) Depression of Wet Bulb in Screen, (2A) Depression of Ice Bulb in Screen ] (1) Wet Biulb and Dew Point, (1B) Ice Bulb & Frost Point, (1A) Dew Point
Back: (7) Vapour Pressure, Frost Point, Dew Point [ Brief Instructions, C ] D, TA, TB
Gauge Marks: [       ]
Condition: C2 (Mint but no manual)
Came with: Original gray/black plastic case labeled, "Blundell Harling Humidity Slide Rule Mk 6A - Celsius