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Dead medium: the Slide Rule
From: (Paul Di Filippo)
Source(s): *K&E Slide Rules, A Self Instruction Manual* by Lyman M. Kells, Ph.D., Professor Emeritus of Mathematics, Willis F. Kern, Former Associate Professor of Mathematics, and James R. Bland, Professor of Mathematics, All at the United States Naval Academy. Published by Keuffel and Esser Co., New York, Hoboken, Philadelphia, Detroit, Chicago, Milwaukee, St. Louis, Dallas, Denver, San Francisco, Los Angeles, Seattle, Anchorage, Toronto, Montreal. Copyright 1943, 1945, 1947, 1955.

Pages 113-115


"Since logarithms are the foundation on which the slide rule is built, the history of the slide rule rightly begins with John Napier of Merchiston, Scotland, the inventor of logarithms. In 1614 his "Canon of Logarithms" was first published. In presenting his system of Logarithms, Napier sets forth his purpose in these words:

"'Seeing there is nothing (right well beloved Students of Mathematics) that is so trublesome to mathematical practice, nor doth more molest and hinder calculators, than the multiplications, divisions, square and cubical extractions of of great numbers, which besides the tedious expense of time are for the most subject to many slippery errors, I began to consider in my mind by what certain and ready art I might remove these hindrances.'

"From Napier's early conception of the importance of simplifying mathematical calculations resulted his invention of logarithms. This invention in turn made possible the slide rule as we know it today. Other important milestones in slide rule history follow.

"In 1620 Edmund Gunter, of London, invented the straight logarithmic scale, and effected calculation with it by the aid of compasses.

"In 1630 William Oughtred, the English mathematician, arranged to Gunter logarithmic scales adapted to slide along eash other and kept together by hand. He thus invented the first instrument that could be called a slide rule.

"In 1675 Sir Isaac Newton solved the cubic equation by means of three parallel logarithmic scales, and made the first suggestion toward the use of an indicator.

"In 1722 John Warner, a London instrument dealer, used square and cube scales.

"Circular slide rules and rules with spiral scales were made before 1733, but their inventors are unknown.

"In 1775 Thomas Everard, an English Excise Officer, inverted the logarithmic scale and adapted the slide rule to gauging.

"In 1815 Peter Roget, an English physician, invented a Log Log scale.

"In 1859 Lieutenant Amadee Mannheim, of the French Artillery, invented the present form of the rule that bears his name.

"Cylindrical calculators with extra long logarithmic scales were invented by George Fuller, of Belfast, Ireland, in 1878 and Edwin Thacher, of New York, in 1881.

"A revolutionary slide rule construction, with scales on both the front and back surfaces of body and slide and with a double-faced indicator referring to all scales simultaneously, was patented in 1891, by William Cox, who was mathematical consultant to Keuffel and Esser Co. With the manufacture of Mannheim rules and this new rule, K&E became the first commercial manufacturer of slide rules in the United States.


"Many types of slide rules have been devised and made in small quantities for the particular purposes of individual users. Rules have likewise been made specially for chemistry, surveying, artillery ranging, steam and internal combustion engineering, hydraulics, reinforced concrete work, air conditioning, radio and other special fields. However, the acceptance of such rules has been relatively limited.

"The slide rule has a long and distinguished ancestry. The rule described in this manual incorporates the most valuable features than have been invented from the beginning of slide rule history, right up to date."

Paul Di Filippo (