The real answer is:
If you have to ask, you're too young to understand.
A more meaningful answer is:
An expensive stick used to add (or subtract) numbers.
When you add logarithms of numbers, you multiply. Subtract to divide.
When you add logarithms of the logarithms of numbers, you can do
The stick can be made of a number of materials. Cheap ones were plastic.
Better ones were bamboo, or ivory covered bamboo.
Serious geek sliderules had twenty
or more scales. Pat had, of course, a very serious sliderule in 1969.
And of course, serious geeks never get rid of sacred artifacts.
Sliderules became practically obsolete by 1970, by 1974 they were used only
by old-timers. Pat still has his as a symbol of his geekdom.
a good site about collecting slide rules is http://www.sliderule.ca/
Slide Rule Links
- Slide Rule Universe
at Sphere Research Corp. Aptly named, this is one of the best slide rule resources
out there. Extensive background information on a huge number of makers and
models, as well as tons of general background info. They also offer many high
end and a few inexpensive slide rules for sale. A definite must see!
- Dave's House of
Slide Rules has a beautiful collection of slide rules, neatly organized
with plenty of personal collecting tidbits that will entertain any slide rule
- David Crate's Quality Slide
Rules . As David describes it, he offers a slide rule for every taste
and budget with everything from complete mint sets to "gently-used slide rule
current listing of slide rule auctions ending over the next 10 days or so.
- HP Museum has a good
introductory primer on the history and uses of slide rules, as well as some
miscellaneous photos of different rules.
- The Oughtred Society finally has
a website. This is sort of a slide rule historical society, devoted to the
exchange of information between slide rule collectors. Publishes a bi-annual
journal that is an excellent slide rule resource.
- Slide Rule Discussion
Group at Yahoo! is the largest message group I've seen dedicated to slide
rules. It's an excellent resource, both for the ongoing discussions and the
downloadable files not available elsewhere.
PDF June 5, 1995