F.140 Data Sheet MJS-p-0321

K&E, 4013 Thacher, 1907

Serial Number or Date Stamp: 2179

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

General Description: Basic linear simple slide rule

Length of 1 decade = 360 in, and overall scale length = 360 in. The largest physical dimension is 18 in.

Front Scales: R1/R2 D [ C ] D R1/R2

Back Scales:

Notes: Early model 4013 Thacher’s Calculating Instrument; missing original magnifier; great thanks to ISRM for assistance in acquisition

References: JOS 2.1 p22 (1993); JOS 3.2 p38 (1994); JOS 5.1 p25 (1996)

Date Acquired: 09/19/2023