Manufacturer: Halden
Country of Manufacture: England
Type: Calculex (Circular)
Date of Manufacture: 1915+
Scales: (Front) L, A [B, R1, R2]
Scales: (Back) S, A [BI, K1, K2, K3]
Number of Scales: 11
Gauge Points: π, q
Slide Rule made from: Metal Frame with Glass Front and Back
Cursor made from:  
Cursor Lines: 1 front, 1 back
Overall Length of Rule: 6 cm Diameter
Length of Scales:
Depth: 0.7 cm
Weight: 50 gm
Acquired from: Joel Goodman
Date: May 2001
Condition: Good
 Leather case. Good Condition
 Instructions (English). Good condition
 JOS Vol 6, No. 2
 "Joseph Halden: A Slide Rule Manufacturer of Manchester"