# How does a cylindrical slide rule work?

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## How does a cylindrical slide rule work?

Writing a logarithmic scale in a spiral that is then imprinted around the outside of a cylinder allows instrument makers to lengthen the scale.

## 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.

## What are the example of slide rules?

Slide the slide until the number on the D scale which is against 1 on the C cursor is the same as the number on the B cursor which is against the base number on the A scale. (Examples: A 8, B 2, C 1, D 2; A 27, B 3, C 1, D 3.)

## 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 was the first calculator?

Pascaline
Pascaline, also called Arithmetic Machine, the first calculator or adding machine to be produced in any quantity and actually used. The Pascaline was designed and built by the French mathematician-philosopher Blaise Pascal between 1642 and 1644.

## Does anyone use a slide rule anymore?

Though they’re no longer produced, the company still stocks around 1,200 or so and occasionally gets an order for some. Why would anyone still want to buy a slide rule, when inexpensive calculators are so readily available? According to Haase, slide rules are better suited to some functions than are calculators.

## What is the best slide rule ever made?

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!

## How much was a calculator in 1970?

In the early 1970s, calculators could cost several hundred dollars, but by the end of the decade, the price had come down to make them much more affordable and much more commonplace.

## Who first invented calculator?

Texas Instruments
Jack KilbyEdith Clarke
Calculator/Inventors

## What replaced the slide rule?

The slide rule remained an essential tool in science and engineering and was widely used in business and industry until it was superseded by the portable electronic calculator late in the 20th century.

## How are cylindrical slide rules different from Circular slide rules?

Cylindrical Rules. Circular slide rules got somewhat more scale length by wrapping the scales around a circle. Cylindrical instruments, got far greater length by wrapping the scale in a spiral around a cylinder.

## Where can I find stock slide rule photos?

Browse 306 slide rule stock photos and images available or search for protractor or abacus to find more great stock photos and pictures. Made in boxwood by Dring and Fage of Tooley Street, London.

## What is the serial number on a fullers spiral slide rule?

The outer, sliding cylinder is marked near the top: FULLERS SPIRAL SLIDE RULE. Near the bottom is marked: ENTD. STATS. HALL; STANLEY, Maker, LONDON. The bottom is stamped: 1099. The top of the long brass index is engraved: 1099 (/) 98. According to Wayne Feely, these numbers indicate the instrument has serial number 1099 and was made in 1898.

## How big was the Stanley Fuller slide rule?

This Fuller Calculator made in England by Stanley was less than 18″ long including the handle yet due to the spiral layout, its scale was 41 feet long. The slide rule consisted of three concentric cylinders. The outermost cylinder was 6″ long and contained the 41′ log scale.

## How to use a slide rule with pictures?

Slide the C scale so the “1” on the far left (called the left index) is directly in line with that number. Example 1: slide the C scale so the left index is in line with the 2.6 on the D scale. Example 2: slide the C scale so the left index is in line with the 4.1 on the D scale. Slide the metal cursor to the second number on the C scale.

## Which is the first number in slide rule?

Multiplication and division are performed using the C and D scales. Square and square root are performed with the A and B scales. The numbers are marked according to a logarithmic scale. Therefore, the first number on the slide rule scale (also called the index) is 1 because the log of zero is one.

## Which is the left index in the slide rule?

In both cases the left index X:1 or C:1 is placed over the first whole number, either Y:2 or D:2. On a linear scale the value of any number on the X scale as read on Y is increased by 1. On a logarithmic scale, the value on any number on the C scale as read on the D scale becomes a multiple of the number under the index.

## How are the numbers on a slide rule scale spaced?

Unlike an ordinary ruler, the numbers on a slide rule scale aren’t spaced on an even, linear scale. Instead, the numbers are spaced using a special “logarithmic” formula, closer together on one side than the other. This lets you line up the scales to get the answer to multiplication problems, as described below.