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Lighthouses. By Peter D Aberdeen High School, 1999. Lighthouse History. First lighthouses -found around Mediterranean Sea -consisted of fires on top of coastal hills

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Lighthouses l.jpg
Lighthouses

By Peter D

Aberdeen High School, 1999


Lighthouse history l.jpg
Lighthouse History

  • First lighthouses -found around Mediterranean Sea -consisted of fires on top of coastal hills

  • First traditional lighthouse structure -Pharos light of Alexandria constructed around 280 B.C. 280 feet tall -reflectors contained wood fire -could be seen for 35 miles


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Lighthouse History- 2

  • Ancient Lighthouses -Portus, Italy 46 A.D.

    -Boulongne, France

    -Dover, England

    -Genoa, Italy 1139

    -Leghorn 1304

  • First in U.S.

    -Boston Light near Boston Harbor, 1716


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Lighthouse History - 3

  • U.S. lights maintained and upkept by U.S. Coast Guard since July 1, 1939.

  • Worldwide, more than 30,000 lights today

  • First lightship stationed in Thames estuary in 1732


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Fresnel Lens

  • First constructed in 1822 by French physicist A. Fresnel

  • Uses concentric rings of glass prisms to bend and focus light into a narrow beam

  • Often as tall as twelve feet



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Concord Point Light - 2

  • Built in 1827 at the mouth of the Susquehanna River in Havre De Grace

  • 36 foot tower, originally built with tin reflector, upgraded to fresnel lens in 1854

  • Decommissioned in 1975

Link to information on Concord Point Lighthouse and other lighthouses