F.109 Data Sheet MJS-p-0379

Hansch, Proportions Rule, c.1938

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 = 11 in, and overall scale length = 15 in. The largest physical dimension is 16 in.

Front Scales: D [ C C ] 1

Back Scales:

Notes: Oversized proportions rule, graduations in 1/16-in, offered by A.C. and H.E. Hansch of Whippany, NJ; these gentlemen had patents in 1938 in regard to flash half-tone photography; R S stamped on back; very worn label on back for Sheldon Fredericks Advertising, New York, NY.

References: https://henryhansch.com/us-patent-office-2125506-–-april-25-1936-–-how-cool-is-this/

Date Acquired: 03/08/2025