# What is a circular slide rule?

## What is a circular slide rule?

Slide Rules Circular Slide Rules Slide rules that are round offer the length of a 10″ rectangular slide rule in a pocket-sized (roughly 3.6″) format, since the scales are on the circumference of circles.

## How do you use the circular slide rule?

The order does not matter. To multiply two numbers, align one of the numbers to the arrow at 1. Find the other number on the same ring as the arrow and read across to find the result. As expected, 6 x 35 gives the same result as 35 x 6.

Are old slide rules worth anything?

The rarest slide rules are 19th Century hand-engraved instruments such as Palmers Computing Scale (a circular model), first published in 1843, or the cylindrical ‘Thacher’s Patent Calculating Instrument’ slide rules produced by Keuffel and Esser Co in the 1880s. These can run close to \$1,000 in good condition.

### What is the use of slide rule?

The slide rule is used primarily for multiplication and division, and also for functions such as exponents, roots, logarithms, and trigonometry, but typically not for addition or subtraction.

### How does slide rule work?

A slide rule works by adding or subtracting the numerical exponents of numbers for multiplication or division, respectively. Thus, numbers to be multiplied or divided are converted to their logarithmic values and their exponents are added or subtracted.

What is the best slide rule ever made?

From top to bottom: Faber-Castell 2/83N Novo-Duplex: Size 38 x 7 cm, 30 scales, plastic. This model is regarded by some as one of the finest slide rules ever made. Its combination of size, build, sophistication of scales offered and attractive use of colour gives a slide rule that impresses!

#### What are features of slide rule?

Most slide rules have three linear strips of the same length. The strips are aligned in parallel and interlocked so that the central strip can be moved lengthwise relative to the other two. The outer two strips are fixed so that their relative positions do not change.

What is the slide rule in math?

## Why do you need a circular slide rule?

Circular rules offer greater scale length in a smaller physical package, so that you don’t poke the guy at the next desk in the eye with that 20 inch straight rule in your quest for better resolution. Concise circular rules also offer some interesting ‘look-up’ and conversion features to the basic rule for added utility.

## How are scales drawn in slide rule simulator?

All the scales are programmatically drawn based on reverse enginered mathematical equations. As such, no images are used for visualisation (only some decorations).

What’s the name of the aluminum slide rule?

Gilson’s most famous aluminum circular slide rule, with alternating yellow/white stripes and fractional converter/operator scales. This rule was made by Gilson in Florida but was often sold by numerous other companies, including POST, Dietzgen, Tavella, Bruning and others.