A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Roger W. Sinnott
Date: 2017 Dec 15, 17:40 -0500
An amazing collection of slide-rule photos is on Tina Cordon’s site at http://tinas-sliderules.me.uk/Index.HTML I didn’t see a perfect match to yours, but several are close.
For example, click on American Slide Rules, and the very first one shows an Acu Math Mannheim Trig No. 90A, St. Louis, MO, where the upper image is a perfect match for the nine scales on your second side. The back of its sliding part has the same B, K, L, C as yours.
Also under American Slide Rules, ¾ of the way down, is a similar one made by the Frederick Post Co., Mannheim Trig, No. 1457.
Under Japanese Slide Rules, scroll all the way down to see the Uchida Yoko Technical Sales Emblem Series 1091. It is a close match to the other side of yours.
-------Alan S wrote: -----------------
I recently picked up on ebay the following slide rule. It is 10" long, with what looks to me like an unusual scale arrangement.
Reading from top to bottom one side at a time, the following is the arrangement of scales: LLO, LLOO, A. On upper fixed part. On moveable part B, K, L, C. On lower fixed part, LL3, LL2, LL1. On the reverse side, the following scale arrangement. Upper section, T, and DF. On sliding part, CF, CIF, CI, C. On lower fixed part, D, S, ST. Usually, the trig scales, S, T and ST are grouped together, not so here.
The slide rule is marked Made In USA, no makers name in view. The thing itself seven for a used slide rule, appears to have had rough usage, though it is readable and so far as I can tell, it works. Any ideas on or about this creature, and what seems to me to be an unusual scale arrangement of trig scales.
Thanks for your attention and any response.