The slide rule appeared around
1625, soon after the propagation of the logarithms by the Scottish nobleman
Napier in 1614.
Edmund Gunter designed around 1624 the first logarithmic scale, for
multiplication and division by constructing sum and subtraction of scale
distances with a pair of dividers.
William Oughtred, mathematician and parson in Oxfordshire, was the first to
describe in 1632 a circular slide rule in his paper "The Circles of
Proportion and the Horizontal Instrument", but by then the instrument had
already been applied for at least 10 years. During the 17th and 18th
century, many specialized slide rules have been designed by mathematicians and
instrument makers for most diverse applications. They were used for navigation
at sea, land surveying, artillery ballistics, alcohol gauging, and carpenters
calculations. Next to the usual scales for multiplication and division, the
goniometrical scales were included not much later. Late 19th century the dual
log scales were added. Different materials (ivory, wood, metal, and later
plastics) and various constructions were used.
The users eventually appeared to favour a fixed body, a sliding tongue, and a
moving cursor with a hairline. Next to the linear slide rule, also circular
and cylindical shapes were used. On a cylinder one can achieve a very long
effective scale, by applying spiralling or parallel subscales. A longer scale
on a slide rule results in a higher accuracy.
From the second half of the 19th century, the industrial production
of slide rules made the instrument available to all engineers.
When electronic pocket calculators started to rise around 1970 (and especially
the "scientific calculators", like the Hewlett Packard 35 in 1972),
the less accurate and slower slide rule was soon defeated (see here
for a paper on the demise of the slide rule, and its successors).