Slide Rules and Blank Stares

“We used to do that with a slide rule.”

Blank stare. “What’s a slide rule?”

“It’s a device they used before calculators to do division, multiplication, square roots, squares and trig functions.”

Blank stare.

“It looked like a ruler, about a foot long, but it had a part in the middle you could slide back and forth to line up with various scales marked on the upper and lower parts of the slide rule.”

Blank stare.

“There was also a hairline that could slide over the rest of the rule to line up different scales on the rule so you could calculate answers to problems. I had one in high school. It was pretty fast.”

Blank stare.

“Did you ever see Apollo 13? Some of the NASA engineers actually still used them during space flights in the sixties and seventies to calculate trajectory and so forth. There’s a scene where they use one during the crisis. It was faster than any calculator at the time. But when they did the movie in 1995 there were none to be found, so they had to borrow one from a museum to do the scene.”

Blank stare.

“It’s kind of like an abacus, a hand-held mechanical device you can manipulate to make mathematical calculations.”

Blank stare. “And they used this slide rule because . . . ?”

My turn: blank stare.

3 responses to “Slide Rules and Blank Stares”

  1. It has been in excess of 50 years, since I was introduced to the pleasures of the slide rule. I gave a blank stare then, and I still do. My math skills were so weak that I could scarcely even comprehend how to use “of them thar things.” But could it have all been due to poor training in math? Most likely. Could it have been due to the fact that my gifts lay in another area or areas? Surely. But we realize what the aim of the comments are: the lack of knowledge of items prominent in our not too distant past on the part of the more recent additions to the human race.How does one make allowance for such gaps in the awareness of our contemporaries. Well, you obfuscate the problem with lots of words and move on, preoccupied with other matters until they catch up.

  2. Ah, slide rules. Don’t miss them. But a good typewriter, that’s another matter. My kids are about 30 now. About 15 years ago we had some computer problems when one of them needed to type something for school. We pulled out a trusty (and dusty) little portable that we’d been shipping around the globe with us during our many Air Force moves. We opened the case, lined up the paper and left the kids to admire the dated but still amazing technology. Not hearing the familiar tap of the keys, we asked what the problem was. Our befuddled teenagers looked at us and asked, “how do you turn it on?”