Editing Slide rule (section)

===20th century===
[[File:Buzz and his pipe.jpg|thumb|[[Buzz Aldrin]] with slide rule during [[Gemini 12]] mission]]

In the 1920s, the novelist and engineer [[Nevil Shute|Nevil Shute Norway]] (he called his autobiography [[Slide Rule: Autobiography of an Engineer|''Slide Rule'']]) was ''Chief Calculator'' on the design of the British [[R100]] airship for [[Vickers#Aviation|Vickers Ltd.]] from 1924. The stress calculations for each transverse frame required computations by a pair of ''calculators'' (people) using [[Fuller's cylindrical slide rule]]s for two or three months. The simultaneous equation contained up to seven unknown quantities, took about a week to solve, and had to be repeated with a different selection of slack wires if the guess on which of the eight radial wires were slack was wrong and one of the wires guessed to be slack was not slack. After months of labour filling perhaps fifty [[Paper size#Traditional inch-based paper sizes|foolscap]] sheets with calculations "the truth stood revealed (and) produced a satisfaction almost amounting to a religious experience".<ref>{{cite book |last= Norway |first= Nevil Shute |title=[[Slide Rule: Autobiography of an Engineer|Slide Rule]] |year= 1954 |publisher= William Heinemann |location= London |pages= 76–78 }}</ref>

In 1937, physicist [[Lucy Julia Hayner|Lucy Hayner]] designed and constructed a circular slide rule in [[Braille]].<ref>{{Cite journal |last=Witcher |first=C. M. |date=1954-12-01 |title=Physics without sight  |journal=Physics Today |volume=7 |issue=12 |pages=8–10 |doi=10.1063/1.3061483 |bibcode=1954PhT.....7l...8W }}</ref>

Throughout the 1950s and 1960s, the slide rule was the symbol of the engineer's profession in the same way the [[stethoscope]] is that of the medical profession.<ref>{{Cite journal |last=Stoll |first=Cliff |date=2006 |title=When Slide Rules Ruled |url=https://www.jstor.org/stable/26061456 |journal=Scientific American |volume=294 |issue=5 |pages=80–87 |doi=10.1038/scientificamerican0506-80 |jstor=26061456 |pmid=16708492 |bibcode=2006SciAm.294e..80S }}</ref>

Aluminium Pickett-brand slide rules were carried on [[Project Apollo]] space missions. The model N600-ES owned by [[Buzz Aldrin]] that flew with him to the Moon on [[Apollo&nbsp;11]] was sold at auction in 2007.<ref>{{cite web |url=http://historical.ha.com/c/item.zx?saleNo=669&lotIdNo=41035 |title=Lot 25368 Buzz Aldrin's Apollo 11 Slide Rule – Flown to the Moon. ... 2007 September Grand Format Air & Space Auction #669 |publisher=Heritage Auctions |access-date=3 September 2013 |archive-date=3 September 2013 |archive-url=https://archive.today/20130903142931/http://historical.ha.com/c/item.zx?saleNo=669&lotIdNo=41035 |url-status=dead }}</ref> The model N600-ES taken along on [[Apollo&nbsp;13]] in 1970 is owned by the [[National Air and Space Museum]].<ref>{{cite web |url=http://airandspace.si.edu/collections/artifact.cfm?id=A19840160000 |title=Slide Rule, 5-inch, Pickett N600-ES, Apollo 13 |publisher=Smithsonian National Air and Space Museum |access-date=3 September 2013 |archive-date=9 October 2013 |archive-url=https://web.archive.org/web/20131009225758/http://airandspace.si.edu/collections/artifact.cfm?id=A19840160000 |url-status=dead }}</ref>

Some engineering students and engineers carried ten-inch slide rules in belt holsters, a common sight on campuses even into the mid-1970s. Until the advent of the pocket digital calculator, students also might keep a ten- or twenty-inch rule for precision work at home or the office<ref>Charles Overton Harris, ''Slide rule simplified'', American Technical Society, 1961, p. 5.</ref> while carrying a five-inch pocket slide rule around with them.

In 2004, education researchers David B. Sher and Dean C. Nataro conceived a new type of slide rule based on ''[[prosthaphaeresis]]'', an algorithm for rapidly computing products that predates logarithms. However, there has been little practical interest in constructing one beyond the initial prototype.<ref>{{cite web |url=http://www.findarticles.com/p/articles/mi_qa3950/is_200401/ai_n9372466 |archive-url=https://web.archive.org/web/20050510072825/http://www.findarticles.com/p/articles/mi_qa3950/is_200401/ai_n9372466 |url-status=dead |archive-date=2005-05-10 |last1=Sher |first1=David B. |last2=Nataro |first2=Dean C. |title=The Prosthaphaeretic Slide Rule: A Mechanical Multiplication Device Based On Trigonometric Identities |work=Mathematics And Computer Education, Vol. 38, Iss. 1 (Winter 2004): 37–43 |via=Findarticles.com |date=2009-06-02 |access-date=2010-02-20}}</ref>