Editing Fresnel lens (section)

== References ==
{{reflist|refs=
<ref name=appleton-1861>D. Appleton &amp; Co., [https://archive.org/stream/appletonsdiction02appl#page/606/mode/2up "Sea-lights"], ''Dictionary of Machines, Mechanics, Engine-work, and Engineering'', 1861, vol.&nbsp;2, pp.&nbsp;606–618.</ref>
<ref name=brock-1909>H.M. Brock, [[s:Catholic Encyclopedia (1913)/Augustin-Jean Fresnel|"Fresnel, Augustin-Jean"]], ''Catholic Encyclopedia'', 1907–12, vol.&nbsp;6&nbsp;(1909).</ref>
<ref name=chisholm-1911-brewster>{{cite EB1911|mode=cs2|wstitle=Brewster, Sir David|volume=4|pages=513–514}}.</ref>
<ref name=chisholm-1911-lighthouse>{{cite EB1911|mode=cs2|wstitle=Lighthouse|volume=16|pages=627–651}}.</ref>
<ref name=condorcet-1790>N. de Condorcet, [https://books.google.com/books?id=o99ZAAAAcAAJ ''Éloge de M.&nbsp;le Comte de Buffon''], Paris: Chez&nbsp;Buisson, 1790, pp.&nbsp;11–12. (This obituary also appeared in ''Histoire de l'Académie Royale des Sciences'' for 1788, printed in 1791.)</ref>
<ref name=gombert-2017>D. Gombert, photograph of the [https://www.flickr.com/photos/gebete29/32970312394/in/photostream/ ''Optique de Cordouan''] in the collection of the ''Musée des Phares et Balises'', [[Ushant|Ouessant]], France, 23&nbsp;March 2017.</ref>
<ref name=musee>Musée national de la Marine, [http://mnm.webmuseo.com/ws/musee-national-marine/app/collection/record/9067 "Appareil catadioptrique, Appareil du canal Saint-Martin"], accessed 26 August 2017; [https://web.archive.org/web/20170826030358/http://mnm.webmuseo.com/ws/musee-national-marine/app/collection/record/9067 archived] 26 August 2017.</ref>
<ref name=ripley-dana-1879>G. Ripley and C.A.&nbsp;Dana (eds.), [https://archive.org/stream/americancyclopae07ripluoft#page/486/mode/2up "Fresnel, Augustin Jean"], ''American Cyclopædia'', 1879, vol.&nbsp;7, pp.&nbsp;486–489.<!-- Contrary to this entry&nbsp;(p.&nbsp;486), calcite and quartz were ''not'' the only doubly refractive crystals known before Fresnel; see (e.g.) Young, 1855, p.{{nbsp}}250 (written 1810) and pp.&nbsp;262, 266, 277 (written 1814), and Lloyd, 1834, pp.&nbsp;376–377. --></ref>
<ref name=tag-2017>T. Tag, [http://uslhs.org/chronology-lighthouse-events "Chronology of Lighthouse Events"], U.S. Lighthouse Society, accessed 22 August 2017; [https://web.archive.org/web/20170408105558/http://uslhs.org/chronology-lighthouse-events archived] 8 April 2017.</ref>
<ref name=tag-fres>T. Tag, [http://uslhs.org/fresnel-lens "The Fresnel lens"], U.S. Lighthouse Society, accessed 12 August 2017; [https://web.archive.org/web/20160722002916/http://uslhs.org/fresnel-lens archived] 22 July 2017.</ref>
<ref name=tag-hyper>T. Tag, [http://uslhs.org/hyper-radial-lenses "Hyper-Radial Lenses"], U.S. Lighthouse Society, accessed 28 February 2021; [https://web.archive.org/web/20210211202401/https://uslhs.org/hyper-radial-lenses archived] 11 February 2021.</ref>
<ref name=tag-prior>T. Tag, [http://uslhs.org/lens-use-prior-fresnel "Lens use prior to Fresnel"], U.S. Lighthouse Society, accessed 12 August 2017; [https://web.archive.org/web/20170520114102/http://uslhs.org/lens-use-prior-fresnel archived] 20 May 2017.</ref>
<ref name=tag-us>T. Tag, [http://uslhs.org/american-made-fresnel-lenses-0 "American-Made Fresnel Lenses"], U.S. Lighthouse Society, accessed 1&nbsp;March 2021; [https://web.archive.org/web/20210221163206/https://uslhs.org/american-made-fresnel-lenses-0 archived] 21 February 2021.</ref>
<ref name=watson-1999>B.&nbsp;Watson, [https://www.smithsonianmag.com/science-nature/science-makes-a-better-lighthouse-lens-170677431/ "Science Makes a Better Lighthouse Lens"], ''Smithsonian'', vol.&nbsp;30 no.{{nbsp}}5 (August 1999), pp&nbsp;30&ndash;31.</ref>
}}