5.16 Post, USA

The Frederick Post Company from Chicago was a major retailer of slide rules in the U.S. Their rules were sold under the Post name, but were produced by other manufacturers.14 Their earliest rules, from about 1900, were made by German companies such as KHH until 1931, and then by Hemmi in Japan. During World War II, the United States being at war with both of these countries meant that Post had to procure rules from US companies, such as Roos, and then re-brand and sell under the Frederick Post Company name. Following the end of the war, Post went back to obtaining rules from Hemmi in Japan until 1975. The Versalog, originally manufactured exclusively for Frederick Post by Hemmi, was designed by three professors at the Illinois Institute of Technology in Chicago, and became one of the premier slide rules sold in the U.S.

Frederick Post Slide Rules.
Frederick Post Slide Rules.

Below is a list of the 31 slide rules in the collection that were sold under the Frederick Post Company name, ordered by Year. A separate listing of Post Rules by Model Number is also available.


Model Maker Year Serial L0 Case Note
1452 KHH 1924 10 yes Post 1452; very early version; maker Koch, Huxhold & Hannemann; Made in Germany in well; leather case, stamped Posts Multiphase Slide Rule; L scale right to left; Slide Rule Data Slips on back
1452 KHH
1925-1930 10 yes Post 1452; maker Koch, Huxhold & Hannemann; Frederick Post Co. Chicago // Germany in well; fine leather case, stamped Posts Multiphase Slide Rule; owner M.J.T.; L scale right to left; Table of Constants The Frederick Post Company on back
1461 Hemmi 1936-1940 10 yes Post 1461 Electronic Engineering rule; elliptical Post logo (only Post with that logo); serif font; 1923 patent; owner Louis E. Herrington, Colorado
1441 Hemmi 1936-43 4 yes + box Post 1441; references to Japan scratched out
1446 Hemmi
1940 10 box Post 1446; newer cursor
1457 Charvoz-Roos 1942 10 no Post 1457; Mannheim-Trig; WW-II; rough condition
1444 Charvoz-Roos 1944-45 5 yes Post 1444-D; pocket Commerce rule; nice condition; made during WW-II; clear celluloid cursor; red leather case; table of fraction conversions on inside of stock; clean table of Equivalents on back
1442 Charvoz-Roos 1945 5 yes Post 1442; distinct C1/D1 C2/D2 scales
1462 Charvoz-Roos
1945 10 yes Post 1462; brown leather case
1441 Hemmi 1947-49 4 yes + box Post 1441; Made in Occupied Japan on inside of leather case and side of cursor
1462 Hemmi 1949-51 10 yes + box Post 1462H; POSTRIG; nice condition but cracked cursor; replaced by Versalog
1444 Bruning
1950 5 yes Post 1444P made by Charles Bruning (on case), no text on back of rule; owner Richard Schroeder
1460 Hemmi 1951 BF 10 box Post 1460; original 1460 box; first year for Versalog; no 258 on stock; 1951 1st edition Versalog book
1460 Hemmi 1952 CL 10 yes Post 1460; case minus flap; Bruce G. Shaw
1460 Hemmi 1953 DC 10 yes Post 1460; leather stitched case; D.P. Hoose
1447 Hemmi 1954 EA 10 box Post 1447
1441 Hemmi 1957 HJ 4 yes Post 1441
1460 Hemmi 1957 HE 10 yes Post 1460; case in nice condition; serial 821829
1460 Hemmi 1958 IL 10 yes Post 1460; case in very nice condition; owner Joseph A. Haertle, General Motors,co-author Computer Modeling in New Vehicle Design, Raymond G. Fischer and Joseph A. Haertle, SAE Transactions, Vol. 93, Section 4: 840772––841109 (1984), pp. 235-240.
1452 Hemmi 1959 JB 10 box Post 1452W; Universal; nice condition; Feb 1959
1447 Hemmi 1962 MK 10 box Post 1447S
1460 Hemmi 1963 NJ 10 yes Post 1460; black case
1461 Hemmi 1965 PG 5 yes + box Post 1461; variant 1b (cos in green); leather case, original box, fact sheet
1447 Hemmi 1966 QJ 10 yes Post 1447; plastic case; instructions
1460 Hemmi 1967 RD 10 yes Post 1460; leather stitched case; K. Stegelman – from daughter
1445 Hemmi 1968 SG 10 yes Post 1445, with 3-ring binder sleeve
1461 Hemmi 1968 SB 5 yes Post 1461; variant 1b (cos in green); brown leather case
1460 Hemmi 1969 TD 10 yes Post 1460 Versalog II, green COS, plastic Post case
1460 Hemmi 1971 VF 10 yes Post 1460 Versalog II, green COS, leather case with clip; came with Versalog II Slide Rule Instructions book
1461 Hemmi 1971 VD 5 yes Post 1461; Versalog II, with A scale; leather case; brand new condition
1460 Hemmi 1972 WF 10 yes Post 1460 Teledyne 44CA-600 Versalog II, green COS, never used (came in original plastic)

  1. While not a “maker” of slide rules, Post is a significant enough retailer that it has been given its own section here.↩︎