Archive
of
Collections
Details and Image
Type
Model No.
Maker
Country
Construction
Material
Date
Scale Length
Area of Use
Pocket Watch Style
Halden's Calculex (v2)
Halden
England
Metal & Glass
1910-1930's
dia. = 6.1 cm
General Purpose
Notes:
Scales on both sides - has larger thumb know to turn the center than (v1)
Image 1
Image 2
