F.319 Data Sheet MJS-p-0166

noID, Engraving Rule, c.1940

Serial Number or Date Stamp:

Country: USA Primary construction material: wd Case included?: no

General Description: Specialty linear ratio/proportion slide rule

Length of 1 decade = 12 in, and overall scale length = 18 in. The largest physical dimension is 20 in.

Front Scales: A [ B P L C ] C’ P

Back Scales:

Notes: 18 inch proportions rule, perhaps used in printing, engraving; maker? American Blueprint? (similar construction to U.S. Military Rule); A/B scales range from 1 to 30, 12 inches from 1 to 10

References: see, e.g., https://sliderulemuseum.com/Lawrence.htm model 10-N

Date Acquired: 12/17/2020