When I read something a friend posted on Facebook about slide rules, it brought to mind an experience I had over a half-century ago while pursuing my B.S. degree on the GI Bill. I worked as an engineering technician at Emerson Electric in suburban St. Louis where I used a slide rule daily. The senior engineer I worked under didn’t trust the results I obtained on my aluminum Pickett & Eckel because he considered it inferior to his bamboo K&E. One day I looked over his shoulder while he was recomputing some of my figures and noticed that all the numbers were worn off the middle of his slide rule.
I said, “Rollo [that was his first name], your slide rule doesn’t have any numbers on it.”
He replied, “Yeah, but I know where they should be.”
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