March 20, 2018, Vol. 24, No. 14

A Slide Rule Discussion Makes St. Paul Paper

Our St. Paul Pioneer Press newspaper has a section called Bulletin Board which is comprised of reader submissions that are not in the ‘Letter to the Editor’ category, but more personal likes, dislikes, recollections, etc., that cover just about any subject matter. This submission of mine may be a bit too much for your purposes, but I thought another slide rule story might interest you. As you can see, it was a response to a previous piece. (Note that we generally sign with a pseudonym for privacy – hence the signature shown.)

Yes. Looking in my 1960 yearbook, I’m pretty sure it was Professor Yanis Inveiss. After 50-some years, I can still picture him in front of the class, but had to check the yearbook for the name.

Walter Pearson
——– Original Message ——–
Subject: Same Answers
Date: Wed, 18 Aug 2010 11:43:43 -0500
From: Walter Pearson <>
To: Bulletin Board Pioneer Press <>

Dear Bulletin Board,

The story by The D in Scandia about students getting the same misspellings based on going to the same church reminds me of when I was in college taking a course taught by an old-school professor from Latvia. He had a thick accent and was somewhat intimidating in his appearance. There were no hellos or goodbyes or any chit-chat in between. We filed silently into his classroom, sat down and immediately started the assignment already on the blackboard. We were pretty much scared to death of him in general.

We often spent the class session individually working on one of his own machine design problems. The textbook problems may have been suitable for some homework, but for class exercises, he liked more difficulty. We were beginning one of these sessions when I realized I had committed the unpardonable sin for an engineering student. I forgot my slide rule in my room and it was just too far away for me to go and retrieve my ‘calculator’ and still get the problem done. I approached him with trembling hands and with some sweat that had that smelly fear odor and told him of my situation. I don’t remember him saying anything, but I did get a look of disappointment that one of his students would do such a thing. He then handed me his own slide rule to use during the class. He also liked to do the problem again while we worked on it in order to double check his calculations and get a feel for where we should be at the end of the hour. Without his slide rule, he wasn’t going to be able to do this.

Near the end of the class, he asked for answers to see if there was some agreement. A few gave their results and he would look at his own answer and shake his head in the negative. I was starting to sweat again thinking he was wondering whether his own calculations might be in error and he might not have caught it because I had his slide rule when he would normally have been rechecking. I now figured I was dead meat anyway, so I raised my hand and offered my result. He changed his expression, pointed to his own paper and nodded in the affirmative. I raised that good old bamboo calculating device in my left hand and pointed to it with my right and said “Same slide rule!”

First he smiled and then started laughing heartily. This was such a departure from his normal demeanor that we were all stunned at first. Then the whole class joined in the laughter. After that I believe he actually softened in tone – without compromising a tough stance on the subject matter – and actually began relating stories of his old country once in awhile. I’m guessing those tough teachers caused us to focus a bit more because the memories of their classrooms seem to be a lot more vivid.

D. Ziner, Rfcsd.
St. Paul


My first job after graduation involved processing large, 31 inch diameter disks used for early random access computer memory. We had to lap the disks to get them as smooth and flat as possible. To get a rough overall view of how flat things really were, we would use a slide projector to beam a horizontal line at a low angle on the disk and view the reflection on a wall. Any micro-hills or micro-valleys would produce a discontinuous image. The best source of those projected lines was from a slide comprised of the glass cursor plate taken out of my old Post Versalog Cat. No. 1460 slide rule. I still have the slide rule, and if I could remember how to use it, I’m sure it would still do its part.

Walter (Don) Pearson, BSME ’62

P.S. If I recall correctly, with that slide rule, we had a method of figuring exactly where the decimal point should be placed. No estimates or guessing needed. I think that was one of the arguments we Post people used against the circular Pickett people.