I never have used a slide rule. (I'm to young I guess) But it
looks like a fascinating thing. I have no clue how they work but I would love to learn it if it makes math more "visual" or logical
[...]
You are adding the log-scaled lengths by sliding the ruler, and reading the sum of the two lengths from the other ruler.
The fly in the ointment is if the numbers, for example, are 3 and 6, then the mark underneath "6" is "1.8". YOU must know the 3*6 is more than ten, and less than 100, to get the correct answer of 18. So the sliderule forces you to think about "orders of magnitude", makes you THINK about the numbers and the answer you're getting.
I have a pocket circular slide rule; it makes that part of the deal even easier. Depending on which way the answer wraps around (clockwise vs. counterclockwise), you shift the decimal point left/right. The back has an L/R/C/frequency nomogram, that you can write on with a pencil and erase with pencil eraser. Very, very convenient. For reasons that escape me at the moment, OS X's calculator takes longer to start up than getting the slide rule out of my pocket. Never mind actually typing the numbers into the calculator.
Cheers, Kuba
