Graphic Calculator, Percentage Calculator, 1962
Serial Number or Date Stamp:
|Country: USA||Primary construction material: pl||Case included?: no|
General Description: Specialty circular ratio/proportion slide rule
Length of 1 decade = 5 in, and overall scale length = 16 in. The largest physical dimension is 6 in.
Front Scales: D [ C ]
Notes: Circular Proportions Rule, made in nearby Barrington, IL
Date Acquired: 08/02/2023