Slide Rule
@flga-2-2 I??ve watched several of Professor Herning??s videos.
Surveying buggy whips
I don't recognize the green instrument in the box. It looks like it might be a Wild unit. What is it?
Surveying buggy whips
I don't recognize the green instrument in the box. It looks like it might be a Wild unit. What is it?
I believe it's a Wild construction level of some type. It's got a long base, it rotates vertically with a vernier. I don't know how to use it, it was purchased at a garage sale.
I don't recognize the green instrument in the box. It looks like it might be a Wild unit. What is it?
It looks like an alidade for plane table topography.
I don't recognize the green instrument in the box. It looks like it might be a Wild unit. What is it?
It looks like an alidade for plane table topography.
you're probably correct, the base would need to rotate on the table, the telescope can sight and read stadia and there is a vertical vernier to turn to the rod.
The table didn't come with the instrument.
I picked this teaching model a few years ago at a local antique store. I have no clue how it works but it looks cool in my office.
I picked this teaching model a few years ago at a local antique store. I have no clue how it works but it looks cool in my office.
It??s pretty simple??the 1 is the index. The scale runs from 1 to 10. Say you want to multiply 2 x 4. You slide the middle 1 on C until it lines up with 2 on D below. Then you find 4 on C on read the answer 8 on D below.
You need to know where the decimal place goes. Most of the time 3 significant digits is the best you can do.
What you are doing is graphically adding logarithms because we know log(2)+log(4) = log(8). Notice that the distances between numbers get smaller as you move to the right.
A and B are for squares and square roots and CI is an inverse scale (runs right to left) for division.
You can use A and B together for simple multiplication and division or you can put your curser on a number on D and read the square on A, same with C and B. Square roots are done the opposite way.
That one is a simple beginner model, mine has log log scales for raising fractional powers and trig scales. I haven??t figured those out yet.
If you multiply something like 25.3 x 145 the answer you read is something like 367 or if you have really good eyes you might see 3668 or 3669. You would have to have an idea the magnitude of your answer to get about 3668 or 3670. So it??s an approximate answer. You would never get 3668.5 unless you had a really expensive specialty rule.
I picked this teaching model a few years ago at a local antique store. I have no clue how it works but it looks cool in my office.
awesome find!
I just searched eBay, found one for $800.
too rich for me, but maybe someday I can find one that fits my budget
I now have a spot on my office wall reserved for one
I'm pretty glad that I missed the age when those were common in math and engineering classes, and we all had basic TI calculators with trig functions by the time I was in middle & high school and college
I paid a little over $200 for this one. I was happy with that price.
