Slip Sticks

Every use a slide rule? Even familiar with what these are? It’s a time that I sorely wish for a clip from an old movie, probably in black and white, with cigarette smoke curling up from an overflowing drafting table, and an engineer slavishly working into the night, shirtsleeves rolled up, figuring with pencil, paper, and a slide rule.

A slide rule is more effective – much more effective – as a visual prop and tool, better than, say, a calculator, or a calculator watch, or a whipping out a smart phone to do a series of calculation. The slip stick just looks cool. Very retro-sheik, yet also allows for the human element. Perhaps that’s the problem with modern calculations.

One of my father’s old slide rules, I recall it from a time when he carried it in his shirt pocket, and I was only about half the length and circumference I am now, one of his artifacts was passed onto me while he was still alive. It’s more a curio than useful computing device.

I slipped it out of its case and ran the slide back and forth. Pie is marked. It’s a Faber-Castell from West Germany, not quite six inches long. Useful to about three points, and probably only sort of useful at that.

It took skill and a sharp eye to properly interpret a slide rule. The little hatch marks like fractions of fractions of an inch, down to a gray fuzz the lines are so fine… Those hatch marks were the answers to log, cosine, or, the best I could do? Multiply and divide. Think I’m strong enough in math skills I could still do some of this in my head, at least, to same degree of accuracy as the slide rule.

Astrology houses, I had a client trying to nail me on the exact degree of the line between houses. I recited the number. I tend to favor Koch instead of Placidus for astrology house systems, but the reason for that is purely technical. That line between houses, like the slide rule, it’s a good approximation. It’s not always the most accurate, but the numbers will be close. There’s a range.

The slide rule was good for getting within a few digits of accurate. Good for getting close. Round numbers. Big picture.

“In the ball park.”