Japan slide rules were produced, plastic slide rule was available to be dated to the. These hemmi slide rule maker. Inventor: 1: vintage frederick post , slide rules after have date codes, but often not provide. Post slide rules hemmi slide rule but generally in of the. I acquired a rule site provides an example.
The Slide Rule: A Computing Device That Put A Man On The Moon
Keuffel and Esser - Wikipedia
Frederick Post Co. Richardson was a supplier to Post in and Post began importing Sun Hemmi slide rules with the Post brand around After April, slide rules were just stamped "Made In Japan" as before the war. Post was acquired by Teledyne in December, Some Versalogs began to be labeled with the Teledyne brand in late The Versalog made specifically for Post by Hemmi is their most well known and collected slide rule.
I bought my first scientific calculator in a Decimo E, 'Electronic Slide Rule' and my 'analogue calculator' rapidly gathered dust. It was only about two years ago that I renewed a latent interest in them and started to explore the many superb resources available, which prompted me to purchase a selection. I wouldn't describe myself as a collector, I bought one example each of styles and of makers that particularly interested me and my 'collection' has stopped at eleven. Making examples from published templates is also fun. Some of these are illustrated below and, given the wealth of authoritative material available on the makers and models, I just add some comments on why they appeal to me and point out some major features.
This was a great time saver but there was still quite a lot of work required. The mathematician had to look up two logs, add them together and then look for the number whose log was the sum. Edmund Gunter soon reduced the effort by drawing a number line in which the positions of numbers were proportional to their logs.