The design of the lighthouse light as we know it today, originated
at the beginning of the 18th Century. The French inventor Augustin
Fresnel had correctly deduced that light was pure energy that traveled
in waves, and he then spent his life developing lenses and reflectors
that could capture and concentrate light. The first lighthouse
optics that he designed combined highly polished prisms with an
array of lenses that captured light and concentrated it back into
a main beam. The design was concentric in arrangement, funneling
the light into a beam that was many times brighter than its source.
This light could be seen for more than 20 miles. Fresnel’s
design of concentric glass rings to concentrate light is still
used today in the production of automobile headlights, traffic
signals and projectors. Many of today’s lighthouses have
a system of rotating lenses, and the newer ones flash off and on
as a way of conserving energy.
 Related
Web Sites |
- Lighthouses
and the Fresnel Lens -
This Web site gives a brief description of the Fresnel
lens, along with additional Web links where you can find
more information about the Fresnel lens.
- National
Park Service: Lighthouse Heritage Web site -
Index to Maritime Heritage Program lighthouse sites, information about preservation
of lighthouses, inventories and surveys of lighthouses, and frequently asked
questions can all be found at this Web site.
- National
Park Service: Lighthouses -
Lighthouses to visit listed by state and region.
- Science,
Optics and You: How Does it Work? Lighthouses -
How lighthouses work is described along with a list of lighthouse activities
for students.
- Smithsonian
National Museum of American History: Lighthouse postcards - “This
online collection showcases the lighthouse postcards
in the Engineering Collections at the Smithsonian's National
Museum of American History. It includes
digitized images of 272 postcards, general information on the U.S. and Canadian
lighthouses represented in the collection, and customized nautical charts provided
by the National Oceanographic and Atmospheric Administration.”
- US
Lighthouse Society - “The
United States Lighthouse Society is a non-profit historical
and educational organization incorporated to educate, inform,
and entertain those who are interested in America's lighthouses,
past and present.”
|
 Further
Reading |
- Crompton,
Samuel Willard. The ultimate book of lighthouses:
history, legend, lore, design, technology, romance. San Diego,
CA, Thunder Bay Press, c2000. 256 p.
- Fleming,
Candace. Women of the lights. Morton Grove, IL, A. Whitman,
1996. 71 p. (Juvenile).
- Jones,
Ray. The lighthouse encyclopedia: the definitive
reference. Guilford, Conn., Globe Pequot Press, c2004. 274 p.
- Lighthouses
of the world. Compiled by the International Association
of Marine Aids to Navigation and Lighthouse Authorities.
Old Saybrook, CT, Globe Pequot Press, c1998. 164 p.
- Lighthouses
and the age of engineering: The nineteenth century. (In)
Naish, John Michael. Seamarks: their history and development.
London, Stanford Maritime, 1985. 192 p.
|
 For
more print resources...
Search on "beacons",
"lenses," "lighthouses. The term, "lighthouses,"
may be subdivided by geographical area, e.g.,"lighthouses--Chesapeake
Bay," "lighthouses--Florida," and "lighthouses--Italy."
in the Library of Congress Online
Catalog.
|
Fire
Island lighthouse and keeper's
5
year
old son. Prints & Photographs
Division,
Library of Congress.
The
lighthouse and cathedral, Marseilles, France. Prints & Photographs,
Library of Congress
St. Augustine
Lighthouse, Anastasia Island, Florida.
Prints and Photographs Division, Library of Congress.
Leaving Stepping Stones Lighthouse.
Prints and Photographs Division, Library of Congress.
Light House for
South West Ledge, L.I. Sound. Prints & Photographs,
Library of Congress
Happy Hooligan Theatrical Poster.
Prints & Photographs, Library of Congress. |
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