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.
Can I still buy a slide rule?
There are many pages about slide rules on the web, and you can still buy brand new slide rules (40 years old but never used, and still in their factory supplied box) in various places.
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.
Who made the best slide rules?
OTIS KING, a London engineer, wrapped several feet of scales around a pocket-size cylinder in 1921 to achieve a portable slide rule with impressive resolution. FABER-CASTELL 2/83N slide rule is considered by some to be the finest and most beautiful slide rule ever made.
Who invented the circular slide rule?
William Oughtred
About 1622, William Oughtred (Figure 1, right), an Anglican Minister, today recognized as the inventor of the slide rule in its actual form, by placing two such scales side by side and sliding them to read the distance relationships, thus multiplying and dividing directly. He also developed a circular slide rule.
Do engineers still use slide rules?
The slide rule is gone but not lost. This gallery illustrates why. There was a time not that long ago when every type of engineer had a slide rule. But the advent of semiconductor technology and the creation of handheld computers made the slide rule obsolete.
How do you read a circular slide rule?
1. Move the beginning (the number 1) on the movable scale (inner circular scale) under the number 2 (multiplicand, first factor) on the fixed scale (outer circular scale). 2. Rotate the pointer to the number 3 (multiplier, second factor) on the movable scale, and read off the result (6) on the fixed scale.
How does a cylindrical slide rule work?
The Fuller calculator, sometimes called Fuller’s cylindrical slide rule, is a cylindrical slide rule with a helical main scale taking 50 turns around the cylinder. This creates an instrument of considerable precision – it is equivalent to a traditional slide rule 25.40 metres (1,000 inches) long.
What is Oughtred’s slide rule?
William Oughtred made the first slide rule by inscribing logarithms on wood or ivory. Before the invention of the pocket or handheld calculator, the slide rule was a popular tool for calculations. The use of slide rules continued until about 1974, after which electronic calculators became more popular.
How much did a slide rule cost?
about $395
Yes, the slide rule was a powerful tool until the early l970s, when things began to change. On February 1, 1972, Hewlett-Packard introduced the HP-35, regarded as the first successful scientific pocket calculator. It sold for about $395.
What is Oughtred slide rule?
In about 1622 William Oughtred, an Anglican minister … today recognized as the inventor of the slide rule … places two such scales side by side and slides them to read the distance relationships, thus multiplying and dividing directly. He also develops a circular slide rule.
Who developed the circular slide rule?
William OughtredSlide rule / Inventor
Who invented Sliderule?
How does a Sliderule 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.