Credits

Photographs and historic prints are free-licensed from Wikimedia Commons and are listed below. The meridional section of a Fresnel lens, and the small brand mark, are our own geometric drawings, simplified and not to scale. They are diagrams, not harbour scenes.

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  Boston Light- America's first lighthouse (29850513722).jpg
  by Petty Officer 3rd Class Andrew Barresi, U.S. Coast Guard · Public domain
  8 August 2016. U.S. Coast Guard photograph, public domain. The 27-mile visibility figure in the original caption is the photographer’s caption, not a List of Lights entry used on this site. Kit-safe.
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  Cape Hatteras Lighthouse in snow.jpg
  by National Park Service · Public domain
  National Park Service, public domain. Do not treat the May 2009 file timestamp as the date of the snow. Kit-safe.
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  Eddystone Lighthouse 1890-1900.png
  by Photographer not stated; Library of Congress photochrom · Public domain
  Photochrom, 1890–1900, public domain. Do not repeat the Commons description’s 1822 date or “Plymouth Sound” placing. Kit-safe.
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  Fastnet Rock Lighthouse, Cork (8262872235).jpg
  by Robert French; Lawrence Collection, National Library of Ireland · No known copyright restrictions
  c. 1897–1900. Robert French / NLI, no known copyright restrictions. Caption it as the earlier Fastnet station, not the 1904 granite tower. Kit-safe.
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  Inside the Fresnel Lens of the Tybee Island Lighthouse (33766615286).jpg
  by Tom Driggers · CC BY 2.0
  25 March 2017. Tom Driggers, CC BY 2.0. Identify it as Tybee Island, not as Eddystone or Fastnet. Kit-safe.
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  Hook Head Lighthouse.jpg
  by Athena (Flickr) · CC BY 2.0
  14 December 2007. Athena (Flickr), CC BY 2.0. Do not take historical claims from the Flickr caption; use Irish Lights for the history of the tower. Kit-safe.
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  Bell Rock light house during a storm from the North East - drawn by J.M. W. Turner, R.A.; engraved by J. Horsburgh. LCCN2005688383.jpg
  by Drawn by J. M. W. Turner; engraved by J. Horsburgh · Public domain
  Engraving after Turner, 1869 printing, public domain. Caption it as an engraving, not a photograph. Kit-safe.
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  Minot's Ledge Lighthouse, by J. H. Williams.jpg
  by J. H. Williams · Public domain
  Stereograph, c. 1859–1885, J. H. Williams, public domain. Published as a single-panel crop of the right-hand image. Do not invent a precise year. Kit-safe.
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  Smeaton dovetailing.jpg
  by Samuel Smiles, Lives of the Engineers, volume 2, 1861 · Public domain
  1861. Public domain technical plate. A plan of masonry, not a view of the standing tower. Kit-safe.
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  LIGHTHOUSE TOWER INTERIOR, SPIRAL STAIRCASE - Pigeon Point Lighthouse, State Highway 1, Pescadero, San Mateo County, CA HABS CAL,41-PESC.V,1-13.tif
  by Historic American Buildings Survey · Public domain
  HABS photograph, public domain. Do not use the 2014 digitisation timestamp as the date of the photograph. Kit-safe.

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