Calculators.  We take them for granted now; they are everywhere and often for free.  However, it might come as a surprise to anyone born in the last 40 years that this wasn’t always the case.

Let’s travel back in time to the early 1970s.  Other than grandfather’s clunking mechanical adding machine that usually made its annual appearance during tax season, the closest many of us came to having a calculator was a “slide rule.”  Essentially a mechanical analog computer, these marvelous pieces of metal and plastic could multiply, divide, and perform the functions of exponentiation, roots, logarithms and trigonometry.  They were accurate, but had only about 3 decimal places of precision.  They date back into antiquity by at least several centuries!

At this time, I was starting the electronics program at Dauphin County Technical School, and it was required that all students own a slide rule for use in the electronics classes.  (A very early form of BYOD!)  I’ll not elaborate here on how they work, but we struggled with them for almost half a year.

It was not long before this that the first of the electronic calculators were starting to appear.  (Intel, the famous juggernaut of digital computing, got their start in the early 1970’s making integrated circuits for electronic calculators.)  Some of the students in my class brought them in to school, but were not allowed to use them because not everyone had them.  So not long before the Christmas break that year, we all agreed to make it a priority that everyone would have an electronic calculator for our return to school in January.

In our first class of the new year, our teacher handed out an assignment that required math calculations.  I suppose he just figured we would all get out our slide rules, but to his surprise, instead we got out our electronic calculators.  He made a fuss and told us to put them away, but we all held them up for him to see that everyone had one.  He could no longer argue the parity issue and we were permitted to use them from that day forward.  My slide rule came home that day and never went back to school.  I still have mine as part of my computer museum, and it still works!

Learn more about Harrisburg Academy on our school website.