NOT a K+E slide rule

A startling development: My dad tells me he has the slide rule mentioned earlier, and it's not a K+E at all! It's a Post 1491 (aka Hemmi 257) chemical engineering rule, actually made by Hemmi in Japan.

As you can see, these things looked almost physically identical to K+E rules, except that this model had funky chemistry-related scales on the back instead of trigonometry (which explains some fragmentary memories I had).

Slide Rule Museum

By the way, the Slide Rule Museum I linked to earlier is well worth poking around, even if the Nineties-vintage frame layout makes it less than ideal to navigate. The front page links to a Virtual Slide Rule you can use to simulate an analog computing device using Internet-enabled digital hardware.

For some reason, this page of special-purpose slide charts and cardboard calculators makes me unreasonably happy.